TheRace Face Single Narrow/Wide Chainring. Race Face Single Rings - Now with performance enhancing chain retention technology. Burly enough for DH Racers and Dirt Jumpers, yet light enough for XC/singlespeed. Single Rings are machined from 7075 aluminum and tested in some of the most punishing riding terrain – Built to last. Race Face Single Narrow/Wide Chainring Features Narrow Wide tooth profiling ensures ultimate chain retention Stiff 4mm plate thickness and I-beam construction transfer loads without flexing 7075-T6 aluminum, aerospace grade strength Reversible laser etched graphics. Compatible for 9, 10 and 11 speed. Sizes: 30, 32, 34, 36, 38, 104 BCD (4 bolt) Weights: 37-57g (36T – 50g) More info