Shimano DXR Single Mountain Bike Cassette Sprocket – CS-MX66 Review Posted by GiantPandaisy July 23, 2018 in Drivetrain Components CS-MX66 BMX Cassette Sprocket Single cassette sprocket Sizes: 14/15/16/18T Chrome Plated W/O Spacer & Lockring CS-MX66 BMX Cassette Sprocket. Single cassette sprocket. Sizes: 14/15/16/18T.