TEKTON 25217 Long Arm Hex Key Wrench Set, Inch, 13-Piece [Older Model] Chrome vanadium steel wrenches are heat treated and black-oxide finished Precisely-sized, chamfered ends insert smoothly into fastener head, reducing wear Long arm wrenches provide extra reach and greater torque Hinged case opens flat, making it easier to get wrenches in and out 13-pc. Long arm hex key wrenches (SAE): 3/64, 1/16, 5/64, 3/32, 7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8 in.