crankbrothers SYNTHESIS Alloy XCTPrecise Handling At Full Speed. Wheels sold individually not in sets. Tuned Front and Rear Alloy Wheel System for XC riding and racing. Compliant tuned front wheel improves handling and maximizes grip and control in turns. Wider inner rim width supports wider tire profile in front, increased volume and contact patch, and rounds tire profile to enhance turning. Stiff tuned rear wheel supports peak loads and enhances stability and tracking at speed.