Commonly used together with flat washers to furthur fasten the screws / bolts by more friction force from split lock washers.
Description
M2 to M12 Spring Lock Washers
About Split Lock Washers:
A spring lock washer is an elastic gasket that absorbs vibrations and shocks, improving the stability and safety of the machine. Its main function is to give the stationary nut an elastic force, so that it is more tightly fixed on the connector, and increase the friction between the connector and the fastener to avoid loosening.