In many shops and old time mechanic's tool boxes, one of the the oldest usable tools buried away is the Park Tool FR-3 Sun Tour 4-Prong Freewheel Remover. The FR-3 was first offered in 1986, when Sun Tour devised their four notch system. Any bike recycler, urban or college town shop has to have an FR-3 on hand today, because their are still plenty of functional bikes that have the Sun Tour 4-Notch Freewheel, but there is no other reasonable way to remove one.

Park makes durable tool from heat treated alloy tool steel, featuring a one inch base that fits wrench or bench vise. Thin wall construction allows use without removal of cones and locknuts. Park recommends you always use a skewer or axle nut to hold tool in place for during removal so it stays seated as you apply torque. if you aren't sure if you have a Sun Tour 4-Notch freewheel, you can measure the distance across notches, which are approximately 24mm.