Wheels

The Speed 360 DB rear wheel is designed for speed. Developed with pro teams to set a benchmark for rigidity in the market, the full-carbon disc design provides an aerodynamic solution, ideal for Time Trial and Triathlon riders. - 12k carbon finish - 2-way Fit - tubeless ready rim - Cult ceramic bearings - Center-Lock disc brake hub - Includes rim tape and valve

Designed to elevate ride feel on mixed terrain routes, from tarmac to gravel roads, Sharq is the result of painstaking research, advanced engineering and extensive work in design and testing, to achieve the best performance possible. Sharq wheels have an inner rim width of 25 mm, an effective compromise both for road tires with a minimum width of 30 mm, guaranteeing good aerodynamics and improved rolling resistance, as well as for wider knobby tires, which will have a solid support for off road use. To ensure that the rim can be used for tubeless systems and with inner tubes, it features mini-hooks that provide maximum safety. As is customary for Fulcrum the bridge is not drilled and, therefore, it is tubeless native, without the need for any additional tape. - Full-carbon rim with direct in-mold construction and matte finish, high rim profile 42 - 47mm - Two-Way fit design for tube and tubeless applications - Aluminum hubs with USB ceramic, Adj. Cup and Cone bearing system - Mo-Mag system: No holes on the rim means that the rim is uniform at every point, free from stress points or zones of weakness and, for the clincher profiles no rim tape is required, to the benefit of weight reduction - 24H, 2:1 spoke ratio with straight-pull, stainless steel, double butted spokes - Supports tire widths from 30mm to 65mm

What It Is The definitive mountain wheel. The M6 Series defines the modern and varied interpretation of the mountain bike. Loaded with traction and acceleration on the climb, it's also backed with precision and control while absorbing vibrations and impacts on the descent. The M6 Series is designed in two diameters and three widths to ensure your sophisticated preference for tire size and pressure is met with an uncompromising tire-to-rim interface. Who It's For The mountain biker who wonders what is possible, the skeptic afraid of "plastic" wheels, the weight weenie, the Clydesdale, the high-mileage guy, the weekend warrior. It would be easier to describe who it is not for… Why We Made It ENVE showed the world that a mountain bike wheel could be carbon — we're still immensely proud of that achievement. A mountain bike wheel, however, can be so much more. The M6 Series is not about technical challenges, and we refuse to chase specifications in order to be the widest, tallest, or stiffest. For the M6 Series of wheels, the question was not about carbon, rather, "What is the potential of a mountain bike wheel?" Each M6 Series wheel model is designed for the broad range of tire widths, hub configurations, and sizes so that you, the modern trail rider, can choose between them.

- Lighter, wider, stronger and more flat resistant - Ride Tuned – Smoother ride improves tracking, control, and reduces fatigue - Wide hookless bead dissipates impact energy and prevents pinch flats. - 30% increase in impact toughness, 60% more flat resistant - Optimized for 2.3-2.5" tires

What It Is The definitive mountain wheel. The M6 Series defines the modern and varied interpretation of the mountain bike. Loaded with traction and acceleration on the climb, it's also backed with precision and control while absorbing vibrations and impacts on the descent. The M6 Series is designed in two diameters and three widths to ensure your sophisticated preference for tire size and pressure is met with an uncompromising tire-to-rim interface. Who It's For The mountain biker who wonders what is possible, the skeptic afraid of "plastic" wheels, the weight weenie, the Clydesdale, the high-mileage guy, the weekend warrior. It would be easier to describe who it is not for… Why We Made It ENVE showed the world that a mountain bike wheel could be carbon — we're still immensely proud of that achievement. A mountain bike wheel, however, can be so much more. The M6 Series is not about technical challenges, and we refuse to chase specifications in order to be the widest, tallest, or stiffest. For the M6 Series of wheels, the question was not about carbon, rather, "What is the potential of a mountain bike wheel?" Each M6 Series wheel model is designed for the broad range of tire widths, hub configurations, and sizes so that you, the modern trail rider, can choose between them.

Top-level all-round full carbon tubeless wheelset with maximum lightness and stunning performances. - 2 Way Fit - Tubeless compatibility - Wider 40mm aero profile for improved aerodynamics - USB Cup&Cone ceramic bearings for great smoothness - MOMAG - Undrilled rim bed for incresead stiffness - 2:1 Spoke Ratio for improved torque balacing - Rim Dynamic Balance for improved balancing - Oversize Flange for better spoke load distribution - Spoke antirotation system for performance consistency

Fastest XC Wheels In the Real World 1240 grams is an obscenely light weight when talking about mountain bike wheelsets, the kind of weight that XC racers dream about. But light weight alone is no longer enough. So, we engineered the new Control SL wheels to be sharp handling, smooth riding, extra durable, and 22% less likely to pinch-flat your tires, in addition to being some of the lightest weight production wheels on the planet. - Rim Type: Carbon clincher, 2Bliss Ready, Zero Bead Hook 4mm FlatTop design. Compatible with tire inserts. - Rim Width: 29mm internal - Front Hub: Alloy body, 15mmx110 thru-axle, 19 and 31mm OD end cap options included. Max Rotor Size <200mm - Front Spoke Pattern: DT Swiss Aerolite Straightpull 294mm, 24-hole, Two-cross - Rear Hub: CNC-machined alloy body, SiNC Ceramic Bearings, premium-quality DT 180 internals and 36t quick engagement ratchet system cassette, includes SRAM XD Driver and 148 end caps. Max Rotor Size <200mm - Rear Spoke Pattern:DT Swiss Aerolite Straightpull 294mm, 24-hole, Two-cross - Bearing Type: SiNC Ceramic Sealed cartridge - Nipple Type: DT Swiss Pro Lock Hexagonal Alloy 14mm 2.0mm - Total Wheelset Weight: 1240g - System Weight Limit: 275lbs/125kg

- Zipp's most advanced and fastest deep-rim wheel for road, triathlon, and time trialing - More than 300 grams lighter that previous model - Optimized tire bed for easy tire installation - Sawtooth rim with Hyperfoil nodes and HexFin ABLC dimple pattern for top aero and crosswind-stability performance with an undulating rim depth - Cognition V2 hubset rolls efficiently whether you are pedaling or coasting. Its Axial Clutch V2 technology reduces drag and lowers friction - Center locking rotor interface. Lockring is included with the wheels - Zipp graphics applied using Zipp's ImPress direct-print technology - Minimum 25mm tire width - Lifetime Warranty

Zipp's 353 NSW Tubeless Disc-brake wheel is the pinnacle of our pursuit of versatility and speed. This wheel fuses Zipp's two most advanced approaches, Sawtooth rim profile and TSE, for an all-encompassing approach to performance. With its undulating 45mm-deep rim shape, the 353 NSW provides speed on every terrain with best-in-class aerodynamic efficiency and crosswind stability. The 353 NSW is Zipp's lightest tubeless wheel yet, making it a fast-puncher ready to fight its way into the breakaway. Zipp's use of hookless (straight side) rims in the 353 NSW is integral to achieving our mission of Making You Faster. With hookless, the transition between the tire and the rim is more seamless and aero. Zipp's hookless rims have more efficient resin distribution, which means lighter wheels. They also are highly durable. Zipp's 353 NSW's Sawtooth rim shape with Hyperfoils optimizes aerodynamic efficiency and crosswind stability. The Sawtooth design also allows the rim to be structurally strong but light. That will help you snap out of corners and maintain that speed no matter the terrain, especially in the steep, punchy stuff. The 353 NSW utilizes Zipp's Total System Efficiency, or TSE, approach to wheel design: overcoming specific barriers to speed: wind resistance, gravity, rolling resistance, and vibration losses. The wheel's 25mm internal width is ideal for running wider tubeless tires at reduced air pressure for a more efficient ride. At the center of the 353 NSW is the Cognition V2 Hubset, re-engineered with an updated Axial Clutch V2 mechanism for quicker engagement and lower friction, as well as improved durability. - Versatile endurance wheel for the modern road bike with tubeless and hookless rim profile - Our lightest tubeless wheel yet, making it a fast-puncher ready to fight - Optimized tire bed for easy tire installation - TSE for greater efficiency and reduced rolling resistance - Sawtooth rim with Hyperfoil nodes and HexFin ABLC dimple pattern for top aero and crosswind-stable performance with an undulating rim depth - Cognition V2 hubset rolls efficiently whether you are pedaling or coasting. Its Axial ClutchV2 technology reduces drag and lowers friction - Ships with 12mm end caps - Center Lock rotor interface. Lockring is included - Zipp graphics applied using Zipp's ImPress direct-print technology - Lifetime warranty

- Zipp’s ultimate road racing wheelset. Aerodynamically efficient and stable in all wind conditions. - Optimized for 28mm tubeless tires at lower pressure for reduced rolling resistance and vibration damping. - Total System Efficiency (TSE) approach addresses wind resistance, gravity, rolling resistance, and vibration losses. - More than 400 grams lighter than its predecessor - Hookless rims for a more seamless and aerodynamic transition between tire and the rim - Cognition V2 Hubset with an updated Axial Clutch V2 mechanism for quicker engagement, lower friction, and improved durability. - Center locking rotor interface. Lockring is included with the wheels - 1360g - Lifetime warranty

Reserve 30 wheels feature a 30mm internal width that supports 2.3-2.5" tires, and the thick rim beads stand up to the abuse of tough, rocky, steep tracks ridden at elite speed. While DH rims see greater single impacts, nothing beats the full weekend of regular abuse that an EWS race dishes out. To say nothing of the infamous 'Anti-Grip' and the rocks buried within the moondust in the Andes of Chile. - Designed for DH riding and racing - Carbon fiber construction with 4mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty - Built with Industry Nine Hubs

Reserve 30 wheels feature a 30mm internal width that supports 2.3-2.5" tires, and the thick rim beads stand up to the abuse of tough, rocky, steep tracks ridden at elite speed. While DH rims see greater single impacts, nothing beats the full weekend of regular abuse that an EWS race dishes out. To say nothing of the infamous 'Anti-Grip' and the rocks buried within the moondust in the Andes of Chile. - Designed for DH riding and racing - Carbon fiber construction with 4mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty

Reserve 30 wheels feature a 30mm internal width that supports 2.3-2.5" tires, and the thick rim beads stand up to the abuse of tough, rocky, steep tracks ridden at elite speed. While DH rims see greater single impacts, nothing beats the full weekend of regular abuse that an EWS race dishes out. To say nothing of the infamous 'Anti-Grip' and the rocks buried within the moondust in the Andes of Chile. - Designed for DH riding and racing - Carbon fiber construction with 4mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty - Built with Industry Nine Hubs

Reserve 30 wheels feature a 30mm internal width that supports 2.3-2.5" tires, and the thick rim beads stand up to the abuse of tough, rocky, steep tracks ridden at elite speed. While DH rims see greater single impacts, nothing beats the full weekend of regular abuse that an EWS race dishes out. To say nothing of the infamous 'Anti-Grip' and the rocks buried within the moondust in the Andes of Chile. - Designed for DH riding and racing - Carbon fiber construction with 4mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty - Built with Industry Nine Hubs

Let’s face it, modern downhill tracks are not for the faint of heart. From the moment you drop in, it’s a hari cari mix of boulders, roots, bumps and jumps awaiting you, and literally the only thing keeping you upright and connecting you to the ground is your wheels. It’s serious business, and the abuse of a day riding DH is no joke, but the Reserve 31 DH wheels have your back. - Designed for DH riding and racing - Carbon fiber construction with 5mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty

The Metron 45 SL TL Disc is the tactical wheelset essential to your quiver. The Metron 45 is an “all-around” wheelset built to take you from climbing all the way to gravel or CX. Victorious on the Cyclocross course, the cobbles of the spring classics, and the torturous mountain stages in the Pro peloton, this wheelset can handle whatever you put them through. - Full Carbon wheelset produced with Vision reliability and high-performance technology - Tubeless ready design, with tubeless valve and rim tape included -45mm depth and 21 mm inner width - P.R.S. alloy hubs with 6 sealed cartridge bearing (2F + 4R) - 21 spoke front, 24 spoke rear, 2:1 laced, Aero bladed straight pull spokes and ABS locking spoke nipples - Artisan built, entirely by hand - Includes spoke protector, cassette spacer, and wheel bag

Reserve wheels are built on the highest quality carbon rims on the market. Everything from the thickness of the rim beads to the external spoke hole reinforcements comes purely from experience of knowing what riders need at every level-from international racing to your local trails. - Built with standard high-quality components including j-bend spokes (28 count) and Sapim mechanically locking nipples - Ships with rim tape installed, tubeless-ready valves, and cards identifying the Santa Cruz builder of each of your wheels - Backed by a lifetime warranty - Built with Industry Nine Hubs

At just under 1750 grams, the Reserve 30SL is one of the lightest trail-ready wheelsets in the line, with no rider weight limit and our uncompromising lifetime guarantee. The Reserve 30SL wheelset is built for you and the way you ride: balanced and responsive to go the distance, delivering uncompromised, untethered trail riding nirvana. - Designed for trail riding - Carbon fiber construction with 3.6mm asymmetric offset - Lower profile for added lateral stiffness with increased vertical compliance - 30mm inner width supports 2.2 to 2.5" tires - Ships with rim tape installed, tubeless-ready valves, and cards identifying the Santa Cruz builder of each of your wheels - Backed by Santa Cruz lifetime warranty - Built with Industry Nine Hubs

Zipp's 353 NSW Tubeless Disc-brake wheel is the pinnacle of our pursuit of versatility and speed. This wheel fuses Zipp's two most advanced approaches, Sawtooth rim profile and TSE, for an all-encompassing approach to performance. With its undulating 45mm-deep rim shape, the 353 NSW provides speed on every terrain with best-in-class aerodynamic efficiency and crosswind stability. The 353 NSW is Zipp's lightest tubeless wheelset yet, making it a fast-puncher ready to fight its way into the breakaway. Zipp's use of a hookless (straight side) rim in the 353 NSW is integral to achieving our mission of Making You Faster. With hookless, the transition between the tire and the rim is more seamless and aero. Zipp's hookless rims have more efficient resin distribution, which means lighter wheels. They also are highly durable. Zipp's 353 NSW's Sawtooth rim shape with Hyperfoils optimizes aerodynamic efficiency and crosswind stability. The Sawtooth design also allows the rim to be structurally strong but light. That will help you snap out of corners and maintain that speed no matter the terrain, especially in the steep, punchy stuff. The 353 NSW utilizes Zipp's Total System Efficiency, or TSE, approach to wheel design: overcoming specific barriers to speed: wind resistance, gravity, rolling resistance, and vibration losses. The wheel's 25mm internal width is ideal for running wider tubeless tires at reduced air pressure for a more efficient ride. At the center of the 353 NSW is the Cognition V2 Hubset, re-engineered with an updated Axial Clutch V2 mechanism for quicker engagement and lower friction, as well as improved durability. - Versatile endurance wheel for the modern road bike with tubeless and hookless rim profile - Our lightest tubeless wheel yet, making it a fast-puncher ready to fight - Optimized tire bed for easy tire installation - TSE for greater efficiency and reduced rolling resistance - Sawtooth rim with Hyperfoil nodes and HexFin ABLC dimple pattern for top aero and crosswind-stable performance with an undulating rim depth - Cognition V2 hubset rolls efficiently whether you are pedaling or coasting. Its Axial ClutchV2 technology reduces drag and lowers friction - Ships with 12mm end caps - Center Lock rotor interface. Lockring is included - Zipp graphics applied using Zipp's ImPress direct-print technology - Lifetime warranty

Excellent aerodynamics and safe steering behavior for a decisive competitive advantage; the ARC 1100 DiCut wheels are made to go flat out fast. Drag and steering movements are reduced thanks to the AERO+ rim that's been aerodynamically optimized by Swiss Slide- these high-end quality wheels are ready to win.

At only 33mm deep, the Campagnolo Bora Ultra WTO 33 has the shallowest wind tunnel optimized (WTO) rim profile of the Ultra family. Every external component of the wheel has been redesigned to maximize aerodynamic efficiency and reduce weight, saving precious energy, and generating greater speed from the same rider input. - The Bora Ultra WTO 33’s lower weight helps riders to reach heights even faster, change pace instantly, and descend with great speed and confidence - Rims are crafted from Campagnolo’s Hand Made Ultra-Light Carbon (H.U.L.C.) - Rims feature Campagnolo’s mirror-like Luxury (C-LUX) finish - Undrilled 2-Way Fit rim beds allow for perfect tubeless compatibility without rim tape - Carbon fiber front hub body is hourglass shaped to improve aerodynamics, and is securely bonded to a light aluminium hub flange - Integrated radial spoke seats ensure perfect alignment

The Classic Enduro S Carbon Wheelset is designed for demanding trails to all mountain adventures. The holy grail of mountain bike wheelset characteristics can be yours by way of the Enduro S Carbon, with a focus on engagement, serviceability and ride quality. Built with Hydra Classic hubs and laced with conventional spokes, enable riders to rest easy when it’s time for travel or service, and the carbon rim carries a lifetime warranty. Bring a new level of responsiveness, control and style to your ride with the Enduro S Classic Carbon. - Enduro S Carbon rims with 31mm inner width and 28 spokes - 6-Pawl Hydra Freehub Body features 690 engagement points at every .52 degrees, yeilding telepathic control - Traditional and conventional flanged hubshell packed with i9 tech, while using a standard j-bend spoke and nipple - Accommodates tire widths 2.3-2.8"

E30 HD wheelsets offer the perfect balance of stiffness, performance, durability, and weight. Achieve more traction and stability to increase confidence while squaring off turns and diving for the inside lines; these wheels deliver quick acceleration and pop to get the entire bike lofted into the air and carry momentum over the toughest obstacles. - Designed for Trail, all-mountain and enduro E-riding - Reinforced rim bed for impact resistance - Asymmetrical rims build stiffer, stronger and more reliable wheels by improving the bracing angles and equalizing the spoke tensions between the drive and non-drive side spokes. - Rated for e-bike use - Built with Industry Nine Hubs

Reserve 30 wheels feature a 30mm internal width that supports 2.3-2.5" tires, and the thick rim beads stand up to the abuse of tough, rocky, steep tracks ridden at elite speed. While DH rims see greater single impacts, nothing beats the full weekend of regular abuse that an EWS race dishes out. To say nothing of the infamous 'Anti-Grip' and the rocks buried within the moondust in the Andes of Chile. - Designed for DH riding and racing - Carbon fiber construction with 4mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty - Built with Industry Nine Hubs

Reserve 30 wheels feature a 30mm internal width that supports 2.3-2.5" tires, and the thick rim beads stand up to the abuse of tough, rocky, steep tracks ridden at elite speed. While DH rims see greater single impacts, nothing beats the full weekend of regular abuse that an EWS race dishes out. To say nothing of the infamous 'Anti-Grip' and the rocks buried within the moondust in the Andes of Chile. - Designed for DH riding and racing - Carbon fiber construction with 4mm asymmetric offset - Reinforced rim bed for impact resistance - Rated for e-bike use - Ships with rim tape installed, tubeless-ready valves, and cards identifying the builder of each of your wheels - Backed by a lifetime warranty - Built with Industry Nine Hubs

E30 HD wheelsets offer the perfect balance of stiffness, performance, durability, and weight. Achieve more traction and stability to increase confidence while squaring off turns and diving for the inside lines; these wheels deliver quick acceleration and pop to get the entire bike lofted into the air and carry momentum over the toughest obstacles. - Designed for Trail, all-mountain, and enduro E-riding - Reinforced rim bed for impact resistance - Asymmetrical rims build stiffer, stronger and more reliable wheels by improving the bracing angles and equalizing the spoke tensions between the drive and non-drive side spokes. - Rated for e-bike use - Built with Industry Nine Hubs

Following directly in the tire tracks of the Terra CLX, the new Terra CL utilizes the same super-light, incredibly tough rim as our flagship wheel. It's a hook-bead, 33mm deep carbon fiber rim with a 25mm inner width that plays well with tubeless setup and allows you to mount tires anywhere from 28mm to 47mm wide at whatever pressure you feel like running. In a nod to accessibility, durability and real-world serviceability, we opted to use ultra-dependable DT Swiss 350 hubs and lace them to the rims with DT Swiss Competition Straightpull spokes. The net effect of these changes is a wheelset that is almost as light as our incredibly light Terra CLX, offering close to the same benchmark performance but with more easily sourced spokes in the event of some back-of-beyond carnage, all with a price tag that is about half that of our flagship product. - Rim: Terra CLX Carbon Clincher, 700c, Disc Brake, Tubeless Compatible - Rim Details: 32mm Depth, 30mm External Width, 25mm Internal Width; ERD 577mm - Hub: DT Swiss 350 Straight-pull Center Lock, Star Ratchet 36t internals (10 degs), 100x12mm & 142x12mm, Shim. Rd. 11sp Freehub (Convertible freehub ) - Bearing Type: DT Swiss Sealed Steel Cartridge Bearings - Spokes: DT Swiss Competition Race Straightpull, Front: Two-cross (1:1) 24 count, R: 287mm, L: 286mm; Rear: Two-cross (1:1) 24 count, DS: 284mm NDS: 287mm - Nipple: DT Swiss Hex Prolock Al 2.0x14mm - Tire Size: 28mm - 47mm; Max Pressure: 28c-32c: 80psi, 33c – 36c: 65psi, 37c- 47c: 60psi - Weight: Wheelset 1,408g, Front 654g, Rear 754g (including tubeless rim tape and tubeless valve) - Assembly Method: Hand built at every step; from rim layup to the last nipple turn. - Extras: Roval Tubeless Rim Tape and Tubeless Valve, Spare Spoke & Nipple Kit - System Weight Limit: 275lbs / 125kg

At only 33mm deep, the Campagnolo Bora Ultra WTO 33 has the shallowest wind tunnel optimized (WTO) rim profile of the Ultra family. Every external component of the wheel has been redesigned to maximize aerodynamic efficiency and reduce weight, saving precious energy, and generating greater speed from the same rider input. - The Bora Ultra WTO 33’s lower weight helps riders to reach heights even faster, change pace instantly, and descend with great speed and confidence - Rims are crafted from Campagnolo’s Hand Made Ultra-Light Carbon (H.U.L.C.) - Rims feature Campagnolo’s mirror-like Luxury (C-LUX) finish - Undrilled 2-Way Fit rim beds allow for perfect tubeless compatibility without rim tape - Oversized 36 tooth ratchet freehub is fast to engage and very durable, plus it accepts N3W, XDR, HG freehub bodies - Integrated radial spoke seats ensure perfect alignment

Featuring the new generation Ratchet System hubs that are lighter and faster than ever before, along with bladed spokes and the superb wheel build quality and reliability you expect from DT Swiss, the XRC 1200 SPLINE 25 is a race-bred trail machine that loves to go fast. It accelerates like nothing else, tracks like nothing else, and is reliable like nothing else. It is the benchmark for high speeds on any trail, on any gravel road, and in any race — whether that race takes place between the tape or in your head. - SRAM XD MTB cassette-compatible

The new standard in modern day, high performance cross country wheelsets. With its hookless full carbon and tubeless ready rim, the XRC 1200 strikes a perfect balance between lightweight and aggressive riding-readiness. Its intricately machined hubshell is superlight while the 25mm tall rim has the inherent stiffness necessary for efficient riding and to precisely hold a line. Together with the renowned DT Swiss build quality, this wheel really sets the benchmark for going fast up and down, whether it's between the tape or not. - Tubeless ready wide and light carbon rim - 180 Ratchet EXP 36pt hub with straight-pull DT spokes, 3-cross pattern - Factory installed tubless-ready tape - Includes tubeless valve, 6-bolt rotor adapter, XD and MicroSpline freehub bodies, tools and wheel bag