The Shimano Ultegra CS-R8100 cassette is for use with Shimano 12 speed racing bike groupsets. This Shimano Ultegra R8100 cassette is available in different ratios. This Hyperglide+ cassette includes the choice of the 'sweet spot' between the 6th, 7th and 8th sprockets. These are the sprockets most people like to ride on. Shimano 12 speed thus makes it possible to retain the cogs that are most comfortable to ride at average speeds, despite large differences in ratio. Also, Hyperglide+ technology delivers a 1/3rd shorter shifting time compared to previous cassette and chain combinations. The cassettes come with the well-known HG fitting, which is compatible with all Shimano HG 11-speed bodies.