The SRAM Force 1 rear derailleur adopts all the technologies of SRAM 1x MTB to provide the fastest, quietest 1x shifting available. SRAM's unique clutch system eliminates chain slack, providing for smoother, quieter, and more secure chain travel. - A dedicated 1x rear derailleur - EXACT ACTUATION for fast and accurate shifts using SRAM's 1:1 actuation ratio (shifter cable travel: derailleur movement). - 10- and 11-speed compatible - X-SYNC pulley features a 12-tooth design that helps control the chain's lateral movement - X-HORIZON "straight parallelogram" design limits all movement to the horizontal axis, which makes ghost shifting impossible while also reducing shift force - ROLLER BEARING CLUTCH's one-way roller clutch controls chain tension for consistent shifting - Cage Lock technology makes for fast wheel changes or chain installation - Available in Short: 11-26 through 11-28 / Medium: 11-26 through 11-36 / Long 11-32 through 10-42 cage lengths Short Cage: Chain Wrap Capacity (teeth): 18 teeth Largest Cog: 28 Weight: 250 g Medium Cage: Chain Wrap Capacity (teeth): 26 teeth Largest Cog: 36 Weight: 262 g Long Cage: Chain Wrap Capacity (teeth): 32 teeth Largest Cog: 42 Weight: 271 g