SRAM Force 1 11sp Rear DerailleurThe SRAM Force 1 Rear Mech implements all of the shifting accuracy and durability from the SRAM mountain bike derailleur design to provide exceptional off-road performance for cyclocross use.Quiet and Smooth Shifting PerformanceThe internal clutch design eliminates chain slack, making it almost impossible for the chain to fall of the chainring whilst cycling; a real benefit when riding on rough terrain. It also creates a noticeably smoother, quieter and higher performing drivetrain configuration for your bike.Features: Cage Material: Aluminium Pulley Bearings: Steel sealed cartridge bearings Pulley Wheel Size: 12T Speed: 11-Speed Cable Pull Ratio: Exact Actuation Maximum Sprocket Size: Short Cage: 26T; Medium Cage: 36T; Long Cage: 42T Weight: Short Cage: 430g; Medium Cage: 434g; Long Cage: 439gTechnologies: Cage Lock: Wheel removal and installation, as well as chain installation, becomes faster and simpler. Just push the cage forward to create slack and lock it into place. X-Sync: The X-Sync pulley features a 12-tooth design that helps control the chain’s lateral movement Roller Bearing Clutch:  Maximum drivetrain stability even through the most punishing terrain. With Roller Bearing Clutch technology, derailleur bounce and chain slap are eliminated without sacrificing precision. Exact Actuation: Simplified and stabilised shifting over tight cog spacing found on modern cassettes. By using exact cable tension, the end result is the easiest index shifting system to set up and it stays that way. X-Horizon: The ‘straight parallelogram’ design limits all movement to the horizontal axis, which makes ghost shifting impossible while also reducing shift force. For quicker, more exact shifting, the large upper pulley offset design maintains a constant chain gap across all gears.Buy SRAM Components from Chain Reaction Cycles, the World's Largest Online Bike Store.