SRAM PG-970 Road Cassette

"SRAM's R9 Cassette is a 9-speed, Shimano compatible road cassette with a 12-23, 12-26, 11-21 or 11-23 tooth option. Featuring SRAM's Powerglide II(tm) technology, the R9 Cassette boasts a simple design, durable construction, and optimized performance. Its simple design delivers a lightweight, efficient and stiff component, while its durable construction features high quality steel cogs and translucent composite spacer. The steel cogs of the R9 Cassette have been heat treated, ensuring a longer life span. The R9 Cassette also features a durable lock ring, which is made up of 70-75 alloy. Weight: 12-23 (210g), 12-26 (230g), 11-21 (200g), 11-23 (210g)"