Patent ID: 7140275

Claim:
An open end C-wrench for driving a hexagon nut in an open end C-wrench head driven by a conventional separate square ratchet driving tool in the drive position, the open end C-wrench head comprising: first and second upper jaw and third and fourth lower jaws rigidly joined together having surfaces which continuously squarely engage four sides of the hexagon nut being driven when the wrench is in the drive position, the jaws being encompassed within a narrow web body having a wide area within which a small square driving hole centrally centered therein, the surface of the first upper drive jaw sized to squarely contact about fifty percent of a first side of the nut, the surface of the second upper backup jaw that adjoins the first upper drive jaw sized to squarely contact an entire second side of the nut adjacent to the side of the nut, the surface of the third lower backstop jaw that adjoins the second backstop jaw sized to squarely contact an entire third side of the nut adjacent to the second side of the nut, the surface of the fourth lower drive jaw that adjoins the third lower backstop jaw sized to squarely contact about ninety percent of a fourth side of the nut adjacent to the third side of the nut, wherein the wide web body area is located below the third backstop jaw, wherein the square driving hole is centered in the wide web body below the surface of the third lower backstop jaw aligned within a ninety degree angle of the intersecting point of the surface of the lower back stop jaw where it adjoins the fourth lower drive jaw.