Although they resemble adjustable spanners, the basic difference is that the jaws of a wrench are serrated, enabling them to grip and turn objects such as lengths of pipe. The wrench should never be used on good nuts as the jaws can cause damage to the flats.
The jaws of this heavy-duty adjustable wrench open and close by turning a control wheel. Once the jaws have been set to hold an object, as force is applied to the handle, the jaws grip even tighter. The Stillson wrench can also be used as a small cramp.
Also known as a plier wrench or mole grips, the jaws of this versatile tool lock firmly onto an object. By slowly squeezing the handles together while turning the adjusting screw on the bottom of the handle clockwise the jaws lock tight. To release the grip simply pull the release lever.
Available with either fixed or adjustable jaws, this wrench is designed specifically for working on basin and bath tap connectors. Also known as a tap spanner, a basin wrench is double-ended with jaws at 90-degrees to the shaft.
A strap wrench has a leather or canvas strap attached which is wrapped around the pipe. The end of the strap is pulled tight through a slot in the head of the wrench. When force is applied to the handle the pipe is loosened. It is generally used on chrome pipe work to avoid causing damage.