Needing a torque wrench quickly (thank you Amazon for premium delivery), I ordered this key especially trusting the rather favorable comment without seeing the size of the tip was not specified (1/2 ") if not in the picture, visible dimension expanding, there was no adapter for standard bits that I own (3/8"). Not wanting to return this key which also seems "serious", so I had to buy this adapter 1/2 "to 3/8" by the way not easy to find ...