Tappet Adjuster Tool SetIntegrated repositionable wrench handle holds the lock nut while the drivers are used to loosen or tighten the valve adjustment screw8 mm, 9 mm, and 10 mm lock nut sockets; and 3 mm square, 4 mm square, and straight slot type drivers includedAllows precise valve lash adjustment without disturbing the setting when the lock nut is fastenedFits most motorcycles and ATVs with screw-type tappet adjustmentsKnurled knob on adjuster drivers ensure a precise and secure grip