SRAM NX Rear Derailleur - 11 Speed, Long Cage, BlackNX is SRAM's 1x drive train for the masses. All the key functionality features of high end 1x derailleurs are built in. Product Details: Cannot be used with double or triple chainrings Same roller clutch and CageLock features as high end models X Horizon geometry Specifications: Cage Length: Long Chain Wrap Capacity (teeth): 32 Color: Black Drivetrain Speeds: 11 Largest Cog: 42 Rear Der Shifter Compatibility: SRAM X Actuation Rear Derailleur Mount