sram cassette pg 720 powerglideBuilt with only one purpose in mind xploiting gravity to its fullest lap after lap. This downhil Specifications Body For Slim and normal HG Driver Body Brand SRAM Color Black Group Comp Sram SRAM X01 DH drivetrain Item Name PG 720 Powerglide Downhill Item Type Cassette Other Compatible with SRAM 11 speed chains Package '1 1 Ratio 11 13 15 17 19 22 25 Recommended Chain 11 speed Speed 7 speed Teeth 11 25T Weight 276 g