SRAM's Red road chainrings are stamped from 7075 aluminum for low weight and excellent strength. The teeth are ramped and pinned for precision shifting, too. Original equipment on SRAM and Truvativ cranks, they also work well with other drive trains. 7000 series aluminum provides strength and durability Color: Black Material: Aluminum Tooth Count: 50 Ring Position/Type: Outer Drivetrain Speeds: 10 Defined Color: Black Chainring BCD: 110 Use with 34T