Abstract: An adjustable hex wrench structure, in its basic embodiment, requires only two parts: a main body configured with a socket cavity having special modified hex cross-sectional shape, and a user operable clamping screw, traversing a wall of the main body and preferably captivated against loss, with a special pressure disc surface for securing a hex fastener workpiece in place in the modified hex cavity operationally without defacing the workpiece. The main body is made cylindrical in shape and configured with a square driver opening to engage the square end of a conventional socket wrench driver shaft.

Abstract: An adjustable hex wrench structure, in its basic embodiment, requires only two parts: a main body configured with a socket cavity having special modified hex cross-sectional shape, and a clamping screw, traversing a wall of the main body, for securing a hex fastener in place in the socket cavity. In socket wrench embodiments the main body is made cylindrical in shape and configured with a square driver opening to engage the square end of a conventional socket driver shaft. In a dual socket wrench version, two different-sized socket cavities, one in each end region of the main body, provide an overall 2:1 size range: e.g. ¾? to ??; the square driver opening is configured in a central bulkhead in the main body so that, whichever socket cavity is deployed to drive a hex fastener, the square end of the driver shaft can be inserted through the other socket cavity, at the opposite end of the main body, to engage the square driver opening.