Park tool headset pedal wrench hcw632mm head wrench and 15mm pedal wrench our popular and versatile head wrenches feature the park tool proven y head design and all headset wrench openings are lazer cut to ensure a tight accurate fit precise sizing is achieved by high voltage computer controlled lazer technology after heat treat waiting until the wrench is heat treated eliminates shrinkage and expansion of the steel after the wrench is sized it takes longer and costs more but its wort