An E-Clip is a basic form of a Circlip. They have the advantage that they can be inserted from the side of the shaft rather than inserting from the end. Also, each E-Clip has flexibility on the shaft size that it will suit.
Caleb Components supplies metric and imperial E Clips online, please use this link to view our range: https://springfasteners.co.uk/product-category/e-clips/