Shimano RD-M772 XT Shadow Rear Derailleur, GS

M772 'Shadow': lower profile body with direct cable routing, stronger spring, and redesigned bracket to avoid chainstay contact (aluminum B-attachment with a Top-Normal return spring). M771 Traditional: Top-Normal return spring ideal for RapidFire. M770 Rapid-Riase: Low-Normal return spring ideal for DualControl. Wide link parallelogram design increases rigidity and performance. P-body rubber bumper reduces noise and adds durability (M771/770). 4 flouric coated link pivot bushings minimize friction. Aluminum construction with 11 tooth pulleys (sealed bearing tension).