Heat treated alloy tool steel, one inch base fits wrench or bench vise. Thin wall construction allows use without removal of cones and locknuts. Features: Removes four-notch BMX / single-speed freewheel from hubs with 1.37 x 24 TPI threads The FR-6 has four notches approximately 32mm across measured inside to inside and 40mm outside to outside Fits over axles up to 16mm thread diameter Always hold the remover secure to the hub using axle nut or quick release skewer Removes four-notch BMX / single-speed freewheel from hubs with 1.37 x 24 TPI threads For 16t and larger freewheels One inch base fits wrench or bench vise Thin wall construction allows use without removal of cones and locknuts