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Spanners, Sockets and Wrenches.
Terminology

A wrench or spanner is a tool used to provide a mechanical advantage in applying torque to turn bolts, nuts or other hard-to-turn items.

But is it a spanner or is it a wrench? What is the difference?

The answer is; it all depends on where you are in the world - in America, a wrench is what we, in the UK, would call a spanner.

In the USA a spanner is a specialized wrench with a series of pins or tabs around the

circumference. These pins or tabs fit into the holes or notches cut into the object to be turned.

Where in the UK we commonly refer to spanners as either open-ended or ring spanners, an American would call them either an open-end wrench or a box-end wrench.

To avoid complication we will use the term spanner for this type of tool:

And wrench will be used in a fairly random way for other types of tools. Why? Well, tools that were originally developed in America are still referred to as wrenches, for instance a Stillson wrench and a basin wrench, both of which we will come to later.

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