The Shimano XTR RD-M972 'Shadow' specific rear derailleur features a lower profile body with direct cable routing, stronger spring, and redesigned bracket to avoid chainstay contact. It also has a wide link parallelogram design which allows for more rigidity and more precise shifting. It features:

Carbon cage and aluminum B-attachment with a Top-Normal return spring (ideal for RapidFire Shifters)
Wide link parallelogram design increases rigidity and service life
P-body rubber bumper reduces noise and adds durability
4 flourine coated link pivot bushings minimize friction
Aluminum construction with sealed bearing 11 tooth pulleys to reduce wear by alternating tooth contact
Speed: 9 speed

Capacity:
o 45T (SGS Long Cage)
Weight:
o 185 grams (SGS Long Cage)