Spanners are one of the most common hand tools found in any tool bag, box, or kit and are used for fastening and loosening nuts or bolt heads with a hexagonal shape. Spanner tools are also commonly called wrenches, particularly in American English. They are typically made from hardened chrome vanadium steel or beryllium copper. The most common types can consist of a ring-style spanner on one end and an open jaw spanner on the other (a combination spanner), or two open jaw ends (an open-ended spanner).

The ring end recess, if present, is generally a six-point or twelve-point opening. This ring end will most likely match the size of the open jaw end, but always check the size marking each tool. The open jaw is typically offset by 15 degrees to allow for greater freedom of movement during operation, which also allows a higher torque force to be applied to help turn the chosen fastening.

Ratchet spanners include a mechanism that helps the user apply maximum force with minimal effort. The mechanism allows the user to use the spanner to tighten a nut or bolt, then move the handle back to the starting position with the head remaining on the nut or bolt without loosening it.

Spanners are available in a variety of metric (mm) and imperial (in) sizes to allow for greater functionality across a wider range of applications, though adjustable spanners (or shifting spanners) are often a preferred choice because users can increase or decrease the size with ease. Our range includes products from leading brands such as Bahco, Facom, Ega-Master, Stanley, Wera & RS PRO, and are available as individual pieces or as part of a larger spanner set.

How do Spanners Work?

In the case of open-jaw spanners, these tools work by holding the opposite sides of a nut or bolt to channel the physical movement of the user, applying torque force to the fastening so that it can be turned. The same rules apply to ring-style spanners, the only difference being that the ring fully encases the fastening rather than applying force to opposite sides. Depending on the material they are made from, spanners can often withstand large amounts of torque being applied to stubborn fasteners.

What are the Different Types of Spanners

Combination Spanners - A combination spanner will have the open jaw spanner on one end and the ring-style spanner on the other.

Open-Ended Spanners - As the name suggests, these tools have an open jaw at each end, however, they often differ in size.

Ratchet Spanners - Ratchet spanners allow the angle of the tool to be adjusted by the user without removing it from the fastening. Also known as socket wrenches: view our range and ratchet spanner sets in our socket wrenches section.

Ring Spanners - Ring-style spanners have enclosed openings to grip the complete fastening rather than just opposite sides. Double-ended ring spanners often have offset handles to improve access to nuts and bolts.

C Spanners - Also known as hook spanners, these are high-quality tools designed to loosen retaining rings and adjust chains. View our range of C Spanners here.

Who uses spanners?

Spanners are used across many industries, such as automotive, aerospace, construction, and manufacturing, because of their functionality and versatility. They are ubiquitous tools found everywhere from home tool sets to factory floors. For domestic work or DIY purposes, spanners serve an abundance of purposes. We recommend getting a spanner set for the home to ensure that you always have the right sized spanner on hand.