Wrench size

A wrench or spanner is a tool used to provide grip and mechanical advantage in applying torque to turn objects—usually rotary fasteners, such as nuts and

adjustable wrench (US and Canada), is any of various styles of spanner (wrench) with a movable jaw, allowing it to be used with different sizes of fastener

flats will define the size of the spanner or wrench needed. The width across flats indicates the nominal "size" of the spanner. The size is imprinted on the

A socket wrench (or socket spanner) is a type of spanner (or wrench in North American English) that uses a closed socket format, rather than a typical

common spanner (wrench) sizes for metric screw threads. Hexagonal (generally abbreviated to "hex") head widths (width across flats, spanner size) are for DIN