Sockets & Ratchets

A socket wrench is a type of wrench, or tightening tool, that uses separate, removable sockets to fit many different sizes of nuts. more...

It generally includes a ratcheting mechanism that allows the nut to be tightened or loosened with a continuous motion, rather than requiring that the wrench be removed and refitted after each turn. Typically, a lever behind the socket switches the wrench between tightening and loosening modes.

The modern socket wrench, with interchangeable sockets, was invented by an American tool manufacturing employee named Joe Johnson in Milwaukee, Wisconsin. Previously, sockets were attached to the handle, so different-sized nuts required different wrenches. He and a co-worker, William Seidemann, formed the Snap-on Wrench Company, which is now Snap-on Inc. of Kenosha, Wisconsin, a large tool manufacturer.

Sockets are available in different lengths so that a user can access nuts in narrow spaces or that have too much length of the bolt protruding behind them. Extender arms allow access to nuts that are difficult to reach.

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