Cold forged Chromoly construction for high-torque strength, and increased durability. Three-pawl design provides engagement every 12 degrees (30 steps total). ED black center ring with a Nickel plated sprocket ring. Removable with standard 4-prong tool. Cassette Body Type: Threaded Standard 1.37" x 24tpi. Chain Compatibility: 3/32" & 1/2" x 1/8".