Keeps the shifting smooth and easy on pavement or singletrack SRAM® PowerGlide II 8-speed cassettes give you reliable performance, day in and day out The race-proven design and durable, chrome-plated finish help ensure years of hassle-free performance. If youre a rider who needs to run an 8 speed drivetrain, the PG 850 is a great choice for light weight, strength, and quick shifting. Recommended Group: PC 68, PC 58, PC 48.