Plumber wrench

A plumber wrench (or plumber's wrench) is a pipe wrench used to rotate plumbing pipes. It is adjusted to different pipe diameters by rotating the key ring (silver in the picture). Its advantage is that it grips with significant force without needing to engage a nut. However, if used carelessly, it can dent or break the pipe. It can also be used on nuts and other flat engagement points.

The plumber wrench was invented in the year 1888 by Swedish inventor Johan Petter Johansson. His wrench shares some principles with both the Stillson-pattern pipe wrench and the rigid pipe wrench. Nevertheless, it is a decidedly different and improved tool. It allows plumbers to use the wrench rather than a pair of tongs to separate or join pipes. It is not widely known in North America. It is common in Europe, where it may be called a "pipe wrench", "Swedish wrench", or "Swedish pattern wrench".

Johansson also improved the adjustable spanner, patenting in 1891.

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