Sram PG1170 11 Speed Cassette is constructed of light, durable materials and features SRAM's PowerGlide tooth profiles and shift ramps for high shifting performance with a quieter chain/cassette combination..Features: Cassette design for high shifting performance with a quieter chain/cassette combination. Semi-spidered design: light, strong, efficient. Weight: 247g (11-26), 257g (11-28), 366g (11-36) Speeds: 11 Material: Heat Treated Steel Cog Cluster, Aluminum Spider (3 cogs) Lock Ring Material: Aluminum Gear Ratios: 11-25T: 11,12,13,14,15,16,17,19,21,23,25 11-26T: 11,12,13,14,15,16,17,19,21,23,26 11-28T: 11,12,13,14,15,16,17,19,22,25,28 11-36T: 11,12,13,15,17,19,22,25,28,32,36