The new GRX wheel supports gravel rides that are faster, further, and more fun. Wider tyres need wider rims to maintain lateral tyre stability at low air pressures. Shimano studied the complicated relationship between tyre size, rim width, air pressure, and tyre lateral rigidity to optimize the GRX rim width for 32-50c tyres. In addition, we pursued the best balance of rim weight, strength, and profile in order to deliver an exceptional gravel wheel.RX870 gravel tuned 12/11-speed 700c tubeless wheelset offering all the technology of Shimano wheels balancing the best combination of rim weight and strength to deliver an exceptional gravel wheelset32mm high profile full carbon rim for improved aero dynamics and durability25mm internal rim width to accommodate a wider section tyre from 32-50mmEasy to use Centre Lock rotor mount for use with disc brakes24 stainless steel butted and bladed straight pull spokes with a 2-cross lacing pattern improve lateral and torsional (power transmission) r