RaceFace 1x Narrow Wide Chainring - 30t 104 BCD 10-12 Speed 7075 Aluminum PurpleNarrow wide teeth prevent chain drop, updated tooth profile runs quieter Durable 4mm thick 7075 T6 aluminum with reversible laser etched graphics Compatible with 9 11 speed chains, allowing a 1X set up on most any drivetrain (works with SRAM 12sp, but not Shimano 12sp chains) 30T rings are threaded for standard M8x0. 75 chainring bolts TECH SPECS ring type single (anti chain drop) mount 4x104mm teeth 30t oval round round color purple