Park tool freewheel remover tool frheat treated alloy tool steel one inch base fits wrench or bench vise thin wall construction allows use without removal of cones and locknuts fits suntour 2 pin fr 2 fits older sun tour two notch freewheels two notches are approximately 25mm across measured outside to outside alwaysuse a skewer or axle nut to hold remover firmly in placefits atom regina zeus fr 4 fits atom regina splined zeus and some schwinn approved freewheels the fr 4 h