These direct-mount chainrings coincide perfectly with the Comet Modular Crank. The megatooth design allows you to put all of your power through without worrying about dropping your chain. All sizes of these chainrings are steel and range from 26T to 38T. - Megatooth thick thin tooth design for Shimano 12sp mountain chain engagement - Direct mount FSA modular crank model-specific rings - Optimized new 11-speed system