SRAM GX Rear Derailleur - 11 Speed Long Cage Red 1x With Clutch cassettes and freewheels If you want a double

If you want a double sided mount

Bring Another Bike

OD of Cap is ~35 mm

CushCore equipped tire: 35

Compatible with 10-Speed Dyna-sys drivetrains

SRAM GX Rear Derailleur - 11 Speed Long Cage Red 1x With Clutch cassettes and freewheels If you want a doubleGX derailleurs share the key features of higher priced models and are available for 1x11 and 2x11 drive trains. For 1x11 speed drivetrains Type 2. 1 roller bearing clutch in the pulley cage pivot for better chain control X HORIZON design reduces shift force, ghost shifting and cage slap Cage Lock mechanism for easy wheel changes Sealed cartridge bearings Aluminum cage and steel pulleys Specifications Color: Black Largest Cog: 42 Rear Derailleur Mount