The SRAM RED E1 XG-1290 Cassette stands as the pinnacle of X-Range gearing. Engineered specifically for wireless electronic shifting, its unified construction ensures optimal weight efficiency while promoting swift gear transitions. Boasting a gradual progression between cogs, including at least five one-tooth advancements, alongside a 10-tooth start for enhanced gearing breadth, this cassette pairs seamlessly with XDR driver bodies. Crafted with a single-piece machined steel X-DOME design, it prioritizes weight reduction without compromising durability.