The plunger oil carrying ring is mainly composed of a plunger, a spring, a sealing ring and a housing. A plunger is a cylindrical metal rod that connects to other mechanical parts in order to transfer liquid from one container to another. The spring is a helical coil of metal that keeps the seal in place and seals. A seal is a soft, ring-shaped part that fits over the plunger and prevents fluid from leaking. The housing is a metal shell that houses the plunger and seal.