Circlip

A circlip (a portmanteau of 'circle' and 'clip'), also known as a C-Clip, snap ring or Jesus clip,[1] is a type of fastener or retaining ring consisting of a semi-flexible metal ring with open ends which can be snapped into place, into a machined groove on a dowel pin or other part to permit rotation but to prevent lateral movement. There are two basic types: internal and external, referring to whether they are fitted into a bore or over a shaft. Circlips are often used to secure pinned connections.