The SRAM X7 9 Speed Rear Bike Derailleur offers a 1:1 actuation ratio and direct route technology for lighter effort gear shifting. This means that for every unit of cable pulled, the derailleur will move the same amount
 
9 speed rear bike derailleur 
Compatible with 8 or 9 speed bikes 
1:1 actuation ratio for precise gear changes 
6061 Aluminium and Steel cage for tough and lasting performance 
Long Cage Length 
Weight: 235g