The AR40 is the latest addition to the Foundation lineup. Featuring an aerodynamically optimized 40mm rim depth front and rear with a 25mm internal rim width, the AR40 is designed to deliver ultimate versatility for the road ride and racer looking for performance on and off-road.The AR40 features ENVE s reliable carbon construction with patent pending Wide Hookless Bead, which is a design element at the leading edge of the rim that dissipates impact energy and reduces the likelihood of pinch flatting your tubed or tubeless tireUltimate versatility for the on and off-road riderIn line with the SES wheel family, the AR40 was tested and developed in the Mercedes-Benz Formula One wind tunnel to achieve real-world aerodynamic performanceMolded Spoke Hole Technology offers a variety of benefits that ultimately result in a more durable and reliable carbon fiber rim and wheelHookless/Straight-Sidewall Design - Tubeless performance depends on the tire maintaining a light press-fit with the rim on the rim s bead seat diameter. ENVE chooses a hookless tubeless rim profile as it allows for the critical tolerance at the rim s bead seat diameter to be both consistent and accurateInnerdrive represents the pinnacle of hub driven bicycle mechanisms. Oversized steel ratchets are positioned inboard and over the bearings, reducing stress on the axle and bearings while ensuring positive and reliable engagementThe AR40 is designed for use with only tubeless tires greater than 28 mm wideItem SpecificationsCassette Body TypeShimano HG 11/12-Speed RoadColorBlackHub/Brake CompatibilityCenter-Lock DiscISO Diameter622 / Road / 29"Rear Axle12mm Thru x 142mmRim MaterialCarbonRim Width (Internal)25Tire TypeTubeless ReadyValvePrestaWheel Size700c ENVE Composites AR40 Rear Wheel Rear Wheel UPC: 810165978553