Product Info Designed for smooth and fast shifting Gradual gear progression between cogs — at least five one-tooth jumps on 10-28T, 10-30T and 10-33T cassettes — while still offering a wider range 10-tooth start helps provide a wider gearing range Designed to work with an XDR driver body One-piece machined steel X-DOME design for weight savings SRAM Model ID: CS-XG-1290-E1