Campagnolo's Record 11-Speed Cassette has been expertly engineered for unparalleled shifting and maximum power transfer. Its largest 3 cogs are constructed from titanium for light weight, while the other 8 are made of nickel-plated steel for durability. Plus, the cogs are mounted on a light and rigid aluminum carrier, and the cassette is secured to the rear hub with a feathery aluminum lockring.