Adjustable spanner

Geesin (2015)[4] shows that wrenches with screw adjustment of various kinds were well known in the early 19th century and that one by William Barlow in 1808 was prescient.

[4] Geesin[4] and others[5][6][7] document that English engineers Richard Clyburn and Edwin Beard Budding presented some influential new designs in 1842 and 1843.

In 1885 Enoch Harris received US patent 326868[8] for his spanner that permitted both the jaw width and the angle of the handles to be adjusted and locked.

As Geesin 2015 documents,[4] the worm-on-rack type (regardless of which terminology is used to name it) was invented in Britain,[4] and later popularized in Scandinavia via the Bahco/Johansson improvement, before its manufacture in the United States was patented.

[14] Monkey wrenches are another type of adjustable spanner with a long history; the origin of the name is not entirely clear, but Geesin reports that it originated in Britain with a fancied resemblance of the wrench's jaws to that of a monkey's face, and that the many convoluted folk etymologies that later developed were baseless.

In Spain, this kind of spanner is commonly called "llave inglesa", which means literally English key.