The Apex 1 Rear Derailleur is part of SRAM s Apex 1 drivetrain, providing the gear range and efficient shifting you need to go wherever you want. X-Horizon Design with Cage Lock TechnologyCompatible with 11-speed SRAM 1x Road SystemsEquipped with a Roller Bearing ClutchLarge Upper Pulley Offset Automatically Adjusts Chain GapLong Cage Fits up to a 42-Tooth CogThe Apex 1 Rear Derailleur offers the X-Horizon design which shifts faster, eliminates ghost shifting and reduces shift force and chain slap. The welcomed addition of Cage Lock Technology makes wheel removal and instillation easier than ever, and the large upper pulley offset automatically adjusts chain gap. The Apex 1 offers high level performance and exceptional value for money, making it the perfect gateway to 1x setups for those on a budget.