Circlip pliers are tools designed to remove or install a specialized type of clip known as the circlip. These have the appearance of a circle and are formed out of flat steel, plastic, or other materials. The circle is missing a small section, and will have small holes pierced through it on either side of the missing section. Circlip pliers are designed similarly to other pliers, though each arm of the plier terminates in a small peg. These pegs are able to fit into the holes in a circlip, allowing the operator to squeeze the clip together or spread it apart.
Circlips can be used on the outer diameter of dowel or peg, or the inner diameter of a tube or other hole, so the ability of circlip pliers to both squeeze and spread can be important. To this end, circlip pliers are typically designed to easily do one or the other of these tasks. Some are built so that squeezing the handles together causes the pegs to squeeze together like a typical plier. Others will pull the pegs apart from each other when squeezing the handles together, while yet others will be reversible. These unique circlip pliers allow the operator to reposition the handles, to operate in either a squeezing or spreading manner.
Since circlips can come in a variety of sizes and have holes of differing diameters, circlip plier sets are often available. These kits can come with a wide variety of circlip pliers that present a range of peg sizes and head designs. Some will have a straight design, while others will bend at 45° or 90°. This can assist in reaching difficult to access circlips in certain conditions.
In addition to reversible circlip pliers, it may also be possible to find some with interchangeable heads. Like a regular circlip plier set, these can allow a wide range of circlips to be removed and installed. Since many heads with a variety of peg sizes and orientations can be installed to a single handle, the set may take up less space and be easier to move around from job to job.
While it is sometimes possible to remove or install a circlip without the proper plier, the job is typically much easier with the correct tool. Spreading a circlip may be possible with a couple small screwdrivers, though this is more difficult than using a circlip plier, and can result in the clip being bent or ejected and lost.