OTC Tools OTC Stinger 4531 Harmonic Balancer Puller/Installer Set. For easy removal of most harmonic balancers and drive pulleys which are press-fitted onto the crank-shaft. A bearing-centered circular 2/3-way and an assortment of metric and fractional bolts and adapters provide wide coverage. A heavy-duty, 3/4" dia. forcing screw is internally threaded to fit the eight adapters to install harmonic balancers. Adapter sizes included: M16 x 2.0, M14 x 1.5, M12 x 1.5, 1/2"-20, 7/16"-20, 3/4"-16, 5/8"-18, and 9/16"-18. A blow-molded plastic storage case keeps set contents organized and protected from loss.