An interesting small patent adjustable wrench or spanner.

Part marked 'PAT NO 584559' on one side of the lower jaw, this relates to the patent granted in 1947 to Greville Humphris, son of Frank Humphris.

Frank Humphris is known for the 'The Master' and 'The Boss' adjustable spanners and the above mentioned patent appears to be a variation/improvement to this design.

The body is some kind of alloy with a steel lined lower jaw, the upper jaw and thread are solid steel and the lower thumb screw adjuster barrel is also steel with a slot to allow the use of a flat head screwdriver.

A few minor surface knocks, please see images.

All parts move freely.

Only 4¹/₄ inches (108mm) overall length.