Adjustable wrench

An adjustable spanner, shifting spanner, shifter, crescent wrench or adjustable-angle head wrench (American English) is a tool which can be used to loosen or tighten a nut or bolt. It has a "jaw" (the part into which the nut or bolt goes) which is of adjustable size, which allows for different size nuts and bolts to be handled by the same spanner. Compare this to the ordinary spanner which has a fixed size.
See more at Wikipedia.org...

Noun
1. can be changed to different settings
(synonym) adjustable spanner
(hypernym) wrench, spanner
(hyponym) monkey-wrench, monkey wrench

[USA] CHIAVE INGLESE. [USA] CHIAVE A RULLINO. [USA] CHIAVE REGISTRABILE. [USA] CHIAVE REGOLABILE