US Patent 7104166 Multi-purpose locking plier

A clamping device utilizing the mechanism of conventional vise-grip locking pliers comprises an extendable fixed arm and an extendable movable arm, both fitted with threaded holes at one end to attach a wide variety of clamping jaws and accessories. The device is capable of clamping workpieces of various shapes such as rectangular, cylindrical, triangular, and spherical, etc. with adjustable clamping force. It is also capable of clamping workpieces of a broad range of sizes, and capable of clamping a plurality of workpieces at the desired spatial relationship between each other.