RaceFace 9/10/11-Speed Single Ring Compatible for 9, 10 and 11 speed 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; Weight 50g (36T) T size is threaded so there is no need for chain ring nut; Reversible laser etched graphics