With the GPX, we introduced an ultralight graphene wheelset for MTB rally and marathon, featuring a 30mm internal rim width. The new SPR technology is a targeted reinforcement in the spoke hole area, allowing for significant weight reduction without sacrificing stiffness or durability. This new rim improves traction and cornering grip, as well as torsional rigidity, impact resistance, and responsiveness. We quickly completed the testing phase, achieving some top 10 results in the XCM World Cup. This winning wheelset comes equipped with the new Nexo Ratchet Z1 ceramic hubs. Available sizes: 29" Rim material: Graphene with carbon fiber Hookless Finish: UD Multilayer Carbon Fiber PROFILE: 25MM Inner Width: 30mm Outer width: 35mm Tire Compatibility: Clincher, Tubeless Ready Hubs: Nexo Ratchet Z1 24T (48 Teeth option) Bearings: Ceramic Coax Braking system: IS6 Front axle: Boost 15×110 Rear axle: Boost 12×148 Cores: Sram XD Spokes: Sapim Aero CX-Ray Straight Pull Weight (g): 1300 Colors: Black Max weight recommended cyclist (kg): 110 Recommended tire size: 2.20" to 2.40" Included: UST valves, pre-installed rim tape, wheel covers.