SRAM's cranks are strong and tough, ready for any kind of ride. So it's inevitable that pedal strikes and debris will chip away at the end of the crank. SRAM's Carbon Crank Boot is an upgrade that combats the wear and tear that comes with hard riding. The boot protects the crank from surface damage and keeps the rider's style perfectly intact. Injection molded plastic crank arm protection Perfect way to protect your carbon crank investment from scratches and dents from pedal strikes Material: Injection molded plastic Recommended Group: XX1, X01, XX, X0