Get Orion Motor Tech's C-Shaped Hook Wrench and get working on your car, heating system, or pip fittings. Wrench Head Size: 3/4 ″ to 2 ″ (19-51mm), 1-1/4 ″ to 3 ″ (32-67mm), 2 ″ to 4-3/4 ″ (51-121mm), 4-1/2 ″ to 6-1/10 ″ (115-170mm).