What is the SRAM X4 rear derailleur for?

The SRAM X4 is a mechanical rear derailleur compatible with 7, 8, and 9-speed drivetrains, built for reliable shifting on entry-level mountain bikes, commuters, and recreational builds. Its wide compatibility across three speed ranges makes it a practical replacement or upgrade part for a broad range of older and budget-oriented drivetrains. SRAM's proven parallelogram geometry delivers accurate, consistent cable-actuated shifting.

The X4 is the straightforward mechanical choice for any 7, 8, or 9-speed build where reliability and value are the priority. Compatible with SRAM and Shimano 7, 8, and 9-speed shifters and cassettes via standard cable actuation.