RaceFace Turbine Chainrings are designed for optimal shift performance and minimal weight in 11-speed XC, Trail and AM applications. Three times stiffer than Race Face Team chainrings without additional weight gain. CNC-machined from 7075 aluminum. Asymmetrical tooth profiling and up-shift/down-shift zones create smooth and quiet shifting under load. Color: Black. Material: Aluminum. Chainring BCD: 104. Defined Color: Black. Ring Position/TYPE: Outer. Drivetrain Speeds: 11. Tooth Count: 38.