DESCRIPTION & MATERIALS MegaTooth Single Chainrings for 1X Systems (10-11sp) Precision CNC machined AL7075/T6 Long tooth profile enhances chain retention. Thick Thin tooth design for maximum chain engagement. AFTERMARKET SIZES BCD 3-86 for K-Force, SL-K, Afterburner and Comet 3-86 series 28T, 30T, 32T, 34T, 36T BCD 4-104 for 104 symmetrical crank series (FSA, Gravity, Shimano, etc.) 30T, 32T, 34T, 36T BCD 5-110 for 110 5-bolt symmetrical crank series (FSA, Shimano, SRAM etc.) 36T, 38T, 40T, 42T, 44T