Tires

Schwalbe's Marathon Plus is legendary for durability and protection. Their nearly impenetrable 5mm-thick SmartGuard layer almost eliminates flats over the course of the tire's excellent, long life. Whether you're setting out on a cross-country bike tour, cruising on a tandem, or just want peace of mind during your daily commute, the Marathon Supreme is in it for the long haul.

Schwalbe's Marathon Plus is legendary for durability and protection. Their nearly impenetrable 5mm-thick SmartGuard layer almost eliminates flats over the course of the tire's excellent, long life. Whether you're setting out on a cross-country bike tour, cruising on a tandem, or just want peace of mind during your daily commute, the Marathon Supreme is in it for the long haul.

Schwalbe's Marathon Plus is legendary for durability and protection. Their nearly impenetrable 5mm-thick SmartGuard layer almost eliminates flats over the course of the tire's excellent, long life. Whether you're setting out on a cross-country bike tour, cruising on a tandem, or just want peace of mind during your daily commute, the Marathon Supreme is in it for the long haul.

Lighter, faster, and longer lasting The all-new R3 Hard-Case Lite road tire rolls faster, with added traction, and a longer-lasting tread. The proprietary TR-Speed compound and updated Hard-Case Lite puncture protection increase both speed and durability while the lightly treaded design adds traction. With R3 you get a faster road racing tire that delivers added confidence through every corner. Product details - Designed for speed, traction, and durability while racing and road riding - Proprietary TR-Speed compound provides confident, fast-rolling performance - Hard-Case Lite with improved Nylon105 beaker belt provides lightweight puncture protection, great ride feel, and extra durability - Fast-rolling, lightly-treaded design adds traction and confidence - Low rolling resistance and excellent cornering grip - Tread styling gets more aggressive as size increases to better suit intended use

Schwalbe's Marathon Plus is legendary for durability and protection. Their nearly impenetrable 5mm-thick SmartGuard layer almost eliminates flats over the course of the tire's excellent, long life. Whether you're setting out on a cross-country bike tour, cruising on a tandem, or just want peace of mind during your daily commute, the Marathon Supreme is in it for the long haul.

Continental's Gatorskin Folding combines 3 flat-protection technologies into one fast-riding, high-mileage racing and training tire. It features a super-fine 180 thread-per-inch casing, a bead-to-bead layer of DuraSkin, and is finished with a Kevlar-reinforced top layer. The result is a tire with a lightweight folding bead that rolls and corners with the best of them while providing flat protection second to none. - DuraSkin sidewall protection - PolyX puncture protection - Weight: 220/240/320/325 grams (23c/25c/28c/32c)

Completely renewed, sporting a dynamic tread pattern design. Matches with a race bike, as well as a classic city road bike. Available in a wide range of dimensions and colors. PureGrip Compound Based on activated silica compounds, this technology was originally intended as an performance level compound, but after intensive development at our Korbach Research and Development Department Facility, an advanced new compound with outstanding grip and cross-country properties was developed. This new rubber mix, given the self explanatory name "PureGrip", is ranked just behind our BlackChili Compound and is being used in our performance products both in the road and mountain bike sectors. Whilst providing great grip, it is also long lasting and highly durable – both characteristics of Continental tires, which are exclusively manufactured in the factory in Hefei (Asia). Suitable for E-Bikes For our E-Bike tyre we fall back on over 100 years' experience with moped and motorcycle tires. All of our city/trekking tires are rated to a standard speed of at least 25 km/h. Those tires marked e50 are also certified for S-Pedelecs. With their high quality structure, puncture protection is high and the rolling resistance is low offering protection from premature wear brought about by the additional driving force.

Continental's Town & Country is a durable workhorse on and off the road, built for stability, traction, and value. Police bike squadrons throughout the world use the Town & Country because of its puncture resistance, high mileage and low rolling resistance. The slick center rolls smoothly on pavement and the recessed tread offers control in the corners.

Get a grip The XR3 Team Issue MTB tire is perfect for riders who want traction and speed in a variety of trail conditions. It has a fast-rolling center tread and aggressive side knobs to keep you rolling fast and confident around corners, plus advanced rubber compound with Inner Strength casing. Great tires for race day or an afternoon out on the trails. Product details - A versatile trail or race tire that excels in a wide variety of conditions - Aggressive side knobs provide consistent cornering and traction across multi-trail surfaces - Lightweight 120 TPI casing and fast-rolling center tread maximize speed and ride feel - Supple and strong Inner Strength casing provides lightweight sidewall protection - Tread depth varies with size for better adaptation to terrain and consistent traction - Tubeless Ready (TLR) design for easy tubeless setup and added puncture protection - Use with Bontrager TLR wheels, sealant, and rim strips for a complete tubeless system designed and tested to work together - 120 TPI - Folding bead - TLR/Clincher

Feel fast, safe, and stable in any weather and on any road on the T1 road touring tire. With super tough nylon casing and durable compound for added wear and traction, this tire is ideal for touring, training, or recreational riding. Key features - Engineered tread design for confidence in wet or dry conditions - Durable compound gives long tread life - Extra-strong nylon casing

At a time when mountain bike tires were unquestionably gum walled, the VelociRaptors came out in black and haven't looked back ever since. They changed the game in 1994 with a steering specific front and a rear that could really dig. The VelociRaptors continue to be popular because to put it simply...they just work. Try riding one of the most classic combos of all time. - Usage: XC / Trail - Conditions: Dry to Wet / Hardpack to Mud - Comp Tube-Type: 829g, DNA compound

The Mezcal is the versatile all-rounder that gets you to the podium, time after time. Ride a combination of terrain? This is the choice of the pros. The Mezcal features a unique low-profile tread that is tightly spaced in the center for low rolling resistance and durability. Countless effective edges work together to grip a variety of terrain, while directional siping on each knob finds traction in the roots and rocks. The best tires are built with the best casing and compound, and the Mezcal is no exception.

Continental Mountain King Tires - All-around performer with uniformly spaced aggressive tread for reliable grip and handling

The Maxxis Ikon is a versatile XC tire designed to perform in a broad range of conditions. With its predictable handling, the Ikon is also a favorite among our slopestyle athletes.

The new standard in enduro tires - Dual-compound - Excellent all-around performance - Tubeless Ready (TR) - Wide trail (WT) casing is optimized for 30-35mm inner width rims The Aggressor is designed for high-speed modern mountain bike trails. Advanced knob shaping creates extra gripping edges, and reinforced side knobs offer enhanced stability when cornering at speed. An all-around trail tire excelling on everything from loose cross country race courses to heavy all-mountain riding.

- For a safer journey. You have full control on icy roads with the Marathon Winter Plus. - For best possible puncture protection, it comes with a SmartGuard layer. - Spikes work best on ice at the minimum pressure - At max pressure, noise is reduced to a minimum on ice-free roads.

Cruise in style with Schwalbe's Big Apple Performance tire. Their wide Balloonbike profile provides natural cushy suspension, and it rolls easily thanks to the smooth tread. Plus, you get their RaceGuard puncture protection and lightweight Endurance rubber compound for confident handling.

The Maxxis Rekon Race is a semi-slick XC race tire that features the lowest profile tread in our XC line. It is a great choice for dry XC trails and short track racing.

Reduced to its essentials. With half the amount of spikes, the Winter provides excellent control on glassy ice. Only in extreme cornering is its big brother Marathon Winter superior. With 50 EPI carcass, reflective lines and K-Guard it offers great benefits at an entry-level price.

- The Cinturato Velo is designed around reliability in bad road conditions and heavy usage as priority and it still keeps Pirelli DNA thanks to its SmartNET Silica compound and confidence-inspiring handling. - Its patent pending Armour Tech construction combines a bead-to-bead high density layer to an aramid breaker and aramid fibers dispersed into the tread. - The SmartNET Silica compound coupled with Pirelli long experience in tread design, adds the safety and handling in any condition, whether it is wet or dry, Pirelli is already famous for.

Tightly spaced knobs for dirt use - Bidirectional - Engineered for BMX tracks, trail riding, and dirt jumping - Front or rear - Full Square-knob design Staggered, tightly spaced center lugs provide control at speed. The knob spacing increases near the shoulder lugs to produce two channels that hook up on both hardpack berms and loose dirt on the trails.

Gravel road riding is all the rage at the moment. It's great for cyclists who want to leave sealed roads behind and enjoy the freedom of cycling on unpaved roads. Designed to suit diverse touring styles, the GravelKing uses a mixture of properties that also accommodate on-road cycling. Featuring ZSG Natural compound, anti-flat Casing, and Advanced Extra Alpha Cord. - Black multi-use gravel tread - Aramid (Kevlar) folding bead

- 3mm thick protective layer - The archetypal high quality touring tire - E-Bike Ready. You can choose every Marathon for your E-Bike (E-25). The main sizes are approved and tested for E-bikes up to 50 km/h (E-50).

Enjoy the velvety smooth ride and sure grip of Electra's quick-rolling Townie Tire. Plus, its classic design adds a touch of style to any bike.

Pasela is Panaracer's standard all around touring or urban commuting tire. Its comprehensive size range ensures that you can find a Pasela for most any usage. Ride it and trust it. - Steel (Wire) bead

Feel fast, safe, and stable in any weather and on any road on the T1 road touring tire. With super tough nylon casing and durable compound for added wear and traction, this tire is ideal for touring, training, or recreational riding. Key features - Engineered tread design for confidence in wet or dry conditions - Durable compound gives long tread life - Extra-strong nylon casing - 30 TPI - Wire bead - Clincher

Tread design offers excellent traction and cornering in just about any terrain without the penalty of high rolling resistance or fast-wearing tread compounds. - A mix of 2, 3, and 5mm center knobs, tall cornering knobs, color stripe on sidewall made of Silica compound for added durability - Zero Slip Grip Natural tread compound integrates more natural rubber to decrease rolling resistance and increase tread wear life

- Unsurpassed all-weather traction. - Modeled after our Assurance All-Season automobile tire, the Transit Tour combines a durable, utilitarian construction with directional siped tread that offers unsurpassed all-weather traction. - Constructed to eBike approved standards and with reflective side strips enhancing twilight and night visibility, the Transit Tour provides robust flat protection along with a comfortable ride for your next journey.

A robust tire with a modern look for city riding - Solid tires for town and city bikes also suitable for tarmac and gravel paths - Good traction from its large contact patch with the terrain - High reliability, best quality: gets you to where you want to go on time!

Premium tire for cold seasons Full control on slippery, snowy roads and dank surfaces thanks to its grippy lamellar tread pattern. Riders of this tire benefit from our know-how as a leading manufacturer of winter tires for cars and trucks. - Vectran breaker for lightweight puncture protection with minimal effect on ride quality - ECE-R75-certified: Recommended for e-bikes up to 50km/h.

Continental Mountain King Tires - All-around performer with uniformly spaced aggressive tread for reliable grip and handling

We named this tire for our friend Nate, who is also quite large and aggressive. This tire has a shred-your-face-off, run-over-anything, kung fu grip knobby tread pattern. The casing is round and supple. Tall, widely-spaced knobs are siped for added grip and compliance. The knobs’ wide spacing means they dig deep and still shed the crap you’re riding through. The tread wraps a little around the sides of the tire, providing good knob contour even on very wide rims, which in turn allows good off-camber traction. Similar to our beer preferences, Nate is available in black and tan. - Folding bead - Max pressure: 30psi

The Rock Hawk is designed as an all-condition trail tire that has an aggressive tread with widely spaced lugs. - Ramped center knobs reduce rolling resistance - Durable 27 TPI casing

Cruise in style with Schwalbe's Big Apple Performance tire. Their wide Balloonbike profile provides natural cushy suspension, and it rolls easily thanks to the smooth tread. Plus, you get their RaceGuard puncture protection and lightweight Endurance rubber compound for confident handling.

A do-anything combination of low rolling resistance, Hard-Case tread and sidewall protection, and a grippy, all-weather compound with siped tread for enthusiasts who want one tire for year-round riding. - Excels on the road in a variety of conditions - Hard-Case triple flat protection protects against punctures

The Maxxis Ardent is a light duty trail tire that rolls fast in dry conditions. For similar rolling speed with improved braking and cornering performance, check out the Rekon.

AW3 is the set-it-and-forget-it tire for road riders and commuters. It rolls fast and keeps the flats away with durable Hard-Case puncture protection. Plus, it's made with a proprietary TR-Endure rubber compound and a lightly treaded design for confidence and traction in all conditions. - Leading puncture protection with traction for confidence in all conditions - Improved Hard-Case puncture protection provides best-in-class defense against flats - Proprietary TR-Endure compound delivers long lasting-traction in all conditions - Smooth-rolling, lightly treaded design with siping channels for traction and all-weather confidence - 60 TPI - Folding bead - Clincher

When you're out on a ride the last thing you want is to be limited by your tires in any way. Surly's ExtraTerrestrial tires were designed to let you ride without limits by following a simple tenet for tire design: make 'em high-volume and kick-ass. The ExtraTerrestrial tire was meant to serve as a heavy-duty off road touring tire that shines on hard pack surfaces. It uses a nylon breaker in the sidewalls for cut protection, a molded pattern for anti-cut propagation, and a Kevlar cap under the tread to protect against flats. The ET tire uses a distinctly directional tread pattern and its width yields more traction than you might expect from a tire with such little rolling resistance. The tread is low profile with a file tread in between blocks. The ExtraTerrestrial tire has enough width and traction for the soft stuff and won't bog you down on smooth or hard surfaces. It's made to be durable and versatile and is at home on tour or on the trail. - Bead Seat Diameter: 559mm - Casing: 60tpi, tubeless-ready bead (928g)

The new standard in enduro tires - Dual-compound - Excellent all-around performance - Tubeless Ready (TR) - Wide trail (WT) casing is optimized for 30-35mm inner width rims The Aggressor is designed for high-speed modern mountain bike trails. Advanced knob shaping creates extra gripping edges, and reinforced side knobs offer enhanced stability when cornering at speed. An all-around trail tire excelling on everything from loose cross country race courses to heavy all-mountain riding.

Biting traction to tame even the most aggressive DH tracks. Our most aggressive DH tire Bontrager's World Cup-winning downhill tire gives you incredible braking control and traction at high speed over aggressive, loose, rocky terrain, wet or dry. The unique G5 tread profile provides maximum bite at any lean angle, with a predictable transition into controlled slides. Product details - A downhill tire that excels in loose, rocky, and wet conditions - Center knob tie-bar increases braking traction - Dual-step shoulder knobs for high lean angle traction - Open tread spacing is self-cleaning - Dual-Ply multi-layer casing adds stability for heavy-duty DH tires with added butyl layer to prevent flats

Keep the rubber side down and fully inflated when you choose MICHELIN's Protek tires. A specially-cut tread pattern reduces rolling resistance, and MICHELIN's rubber compound makes for an excellent grip. Grooves at the shoulders help increase traction on wet and greasy surfaces. A 1mm-thick anti-puncture reinforcement will help ensure nothing bursts your bubble, so you can enjoy the ride. Weights: 26 x 1.4 (630g) 26 x 1.85 (940g)

Cruise in style with Schwalbe's Big Apple Performance tire. Their wide Balloonbike profile provides natural cushy suspension, and it rolls easily thanks to the smooth tread. Plus, you get their RaceGuard puncture protection and lightweight Endurance rubber compound for confident handling.

Cruise in style with Schwalbe's Big Apple Performance tire. Their wide Balloonbike profile provides natural cushy suspension, and it rolls easily thanks to the smooth tread. Plus, you get their RaceGuard puncture protection and lightweight Endurance rubber compound for confident handling.

- Multi-use tire with a smooth center for low rolling resistance and raised lateral lugs for grip - Wire bead - Size: 26 x 1.95

Continental Mountain King Tires - All-around performer with uniformly spaced aggressive tread for reliable grip and handling

Where the rubber high fives the road. Genuine Electra tires, for that genuine Electra feel. These are the tires your Electra was born with. Propelling you along the pavement, boardwalk or anywhere really. Product details - Semi-smooth tread cruiser tire - Tube not included - Tires are sold individually, not as a pair

Feel fast, safe, and stable in any weather and on any road on the T1 road touring tire. With super tough nylon casing and durable compound for added wear and traction, this tire is ideal for touring, training, or recreational riding. Key features - Engineered tread design for confidence in wet or dry conditions - Durable compound gives long tread life - Extra-strong nylon casing - 30 TPI - Wire bead - Clincher

Meet Edna: Surly's latest ultra-versatile fat bike tire. Edna was designed to perform admirably on a wide variety of terrains. Wanna go ride some super loose dirt or snow trails? Do it. Feel like riding over the pulverized bones of your enemies or, as some people call it, sand? Go for it. Hardpack? Lean back and let ‘er rip. Edna’s unique tread pattern has enough lug to provide bite on the loose stuff and a tight center tread that doesn’t drag on the hard. Add in a 4.3” footprint and you have enough traction and float to ride wherever and whenever you damn well please. - Folding bead - Casing: 60 TPI - Max pressure: 30psi - Weight: 1330g

A road tire with Hard-Case Lite puncture protection for long-lasting confidence and traction on every road. Get that new-tire feeling The R1 road tire is the perfect replacement tire for your road bike or urban commuter. It's a great balance of performance and value, with 60TPI casing and Hard-Case Lite puncture protection that keeps weight down and durability up. Product details - Designed for lasting durability and performance for road riding - Hard-Case Lite provides lightweight puncture protection - Low rolling resistance and excellent cornering grip Specifications - Size: 700C x 32mm - Diameter: 700C - Width: 32mm - TPI: 60 TPI - Durometer: 62a - Bead: Wire - Type: Clincher - Max pressure: 50psi - ETRTO: 32-622 - Puncture protection: Hard-Case Lite - Weight: 428g

When you’re out on a ride the last thing you want is to be limited by your tires in any way. Our ExtraTerrestrial Tires were designed to let you ride without limits by simply following the only tenets we have for tire design: they’re high volume and they kick ass. The ExtraTerrestrial tire was meant to serve as a heavy-duty off-road touring tire that shines on hardpack surfaces. It uses a nylon breaker in the sidewalls for cut protection, a molded pattern for anti-cut propagation, and a Kevlar cap under the tread to protect against flats. The ET Tire uses a distinctly directional tread pattern and its width yields more traction than you might expect from a tire with such little rolling resistance. The tread is low profile with a file tread in between tread blocks. The ExtraTerrestrial tire has enough width and traction for the soft stuff and won’t bog you down on smooth or hard surfaces. - Folding bead - Casing: 60 TPI - Recommended rim width: 23 – 30mm

GRAVEL Sometimes the greatest journeys are full of memorable experiences: churning over towering mountain passes, trying to make it to the next town before the café closes, pedaling from sunrise to sunset, or sleeping in when you’re gifted with perfect weather and an incredible view from your tent. We designed the Sparwood around long-distance mixed-terrain routes, for riders seeking to experience the land, not just ride on it. HOW IT WORKS - Center lugs are raised and ramped for rolling efficiency; the diamond-shaped lugs squeeze in for grip as they contact dirt, then back out to shed debris. - Diamond- and chevron-shaped transition lugs feature staggered spacing and height to improve shedding and traction. - L-shaped side lugs dig in for grip while braking through corners, but roll quickly when off the brakes.

The Grand Prix 5000 is the best all-rounder in the field, brought to a whole new performance level. Ride faster, more comfortably, and with increased puncture protection. Its Active Comfort Technology absorbs vibrations and smooths your ride. Lazer Grip technology, designed to make you one with the road, features a lasered micro profile structure that expands over the tire’s shoulder and provides outstanding cornering. The Vectran Breaker is lighter, more flexible and protects more effectively against cuts than comparable nylon. With incredible tear resistance at a very low weight, it possesses exactly the right properties to be a premium puncture protection insert, while not adversely affecting rolling resistance. The Grand Prix 5000—made to make you better. With Continental's unique and legendary BlackChili tread compound, produced only in Germany, they have revolutionized the sport of cycling. This compound answers the eternal question of the best balance of grip and rolling resistance for cycling. Regular test wins confirm the measurable and noticeable advantages for cyclists, established in both the lab and on the road. The latest polymers, as well as specially developed carbon black particles and filler materials, guarantee ultimate performance.

The Grand Prix 5000 is the best all-rounder in the field, brought to a whole new performance level. Ride faster, more comfortably, and with increased puncture protection. Its Active Comfort Technology absorbs vibrations and smooths your ride. Lazer Grip technology, designed to make you one with the road, features a lasered micro profile structure that expands over the tire’s shoulder and provides outstanding cornering. The Vectran Breaker is lighter, more flexible and protects more effectively against cuts than comparable nylon. With incredible tear resistance at a very low weight, it possesses exactly the right properties to be a premium puncture protection insert, while not adversely affecting rolling resistance. The Grand Prix 5000 Tubeless—made to make you better. With Continental's unique and legendary BlackChili tread compound, produced only in Germany, they have revolutionized the sport of cycling. This compound answers the eternal question of the best balance of grip and rolling resistance for cycling. Regular test wins confirm the measurable and noticeable advantages for cyclists, established in both the lab and on the road. The latest polymers, as well as specially developed carbon black particles and filler materials, guarantee ultimate performance.

Puncture protection and mileage are the strengths of Hardshell-ProTection. A wider PolyX Breaker, the specialist against punctures under the tread center and shoulders, provides for great reliability. The three-ply—each layer with 60 TPI—carcass covers the entire tire and makes it a real bastion against urban detritus. The outer sidewalls of the tire are reinforced with DuraSkin fabric, providing even more reliability due to the casing being so well protected. Hardshell tires are the puncture-resistant flagship amongst racing tires—produced exclusively in Germany. - Ideal when it comes to extremely long service life, for the next tour or the commute. - Made for rough surfaces and rugged tarmac.

The XR3 Team Issue Tubeless Ready mountain bike tire is the right choice for high performance over the widest range of trail conditions. Advanced rubber compound and Inner Strength protection make XR3 Team Issue tires Trek Factory Racing's pick for best all-around high-performance for cross country. Key features - Versatile tread provides consistent traction and cornering - Excels in a wide variety of conditions - Tubeless Ready (TLR) tire is engineered for easy tubeless setup and puncture protection - Inner Strength casing is lightweight sidewall protection that's supple and strong

When the weather turns nasty and the pavement becomes treacherous, H2 Hard-Case Ultimate offers protection and performance. Featuring Bontrager's most comprehensive puncture protection in a lightweight package with a fast rolling, versatile tread and reflective sidewalls, this tire is ready for anything. - Excels on pavement - Sub-tread co-extrusion provides maximum puncture protection - Anti-cut, bead-to-bead casing resists cuts from glass and sharp objects - Anti-pinch sidewall support prevents pinch flats - Aramid breaker belt protects against tread punctures - Reflective sidewall strips for added visibility

Continental's ultra-tough Gator Hardshell combines 3 flat-protection technologies into the ultimate distance and training tire. It features a flat-busting, bead-to-bead layer of DuraSkin and an extra-wide Poly-X Breaker anti-puncture strip. But Conti wasn't done yet. They added material in the tread to improve mileage and lend another level of puncture resistance. Plus, the folding bead keeps the weight low. Weight: 23c: 250 grams 25c: 270 grams 28c: 350 grams 32c: 385 grams

For the roads less traveled The GR2 Team Issue gravel tire is designed for fast-rolling performance and biting traction on even the most rugged gravel roads. It has proven success at the most demanding gravel races and features Inner Strength Casting that provides lightweight puncture protection without sacrificing smooth, supple feel. Plus, you can go tubeless for better performance and even more puncture protection. - A gravel tire that provides excellent traction for confidence across the roughest roads - Fast rolling with consistent, predictable traction for a variety of road conditions - Tubeless Ready (TLR) for easy tubeless setup and puncture protection - Supple and strong Inner Strength casing provides lightweight sidewall protection - Lightweight 120 TPI casing provides great ride feel and tire performance

GRAVEL Cannonball is a go-to gravel race tire for normal conditions. The tread pattern features a directional, tight-knit center tread that sheds dirt and debris to decrease rolling resistance, and side knobs for effective cornering traction. Cannonball is built for all-around gravel riders and racers. HOW IT WORKS - Center lugs are raised and ramped for rolling efficiency; the diamond-shaped lugs squeeze in for grip as they contact dirt, then back out to shed debris. - Transitions lugs are spaced out and vary in height to boost traction. - L-shaped side lugs dig in for grip while braking through corners, but roll quickly when off the brakes.

GRAVEL Designed with the unknown in mind, the Rutland takes the guess work out of selecting the right tire for the ride. Ramped, tightly spaced center lugs reduce rolling resistance while larger, more spaced-out shoulder and transition lugs provide grip in loose conditions. HOW IT WORKS - Center lugs are large and widely spaced for braking and acceleration grip, and ramped to lower rolling resistance. - Transition lugs are spaced out to shed mud; siping conforms to the road surface for increased traction in corners. - Side lugs are staggered to provide traction in more aggressive turns and on loose surfaces.