A spring steel ringlike item designed to be placed between a piston ring and the piston to maintain the correct piston ring pressure against the cylinder wall.
NSN 5975-01-362-4177
NSN 6240-01-623-8783
NSN 5950-01-290-3967
NSN 6130-01-521-8865
NSN 5920-01-088-7958
NSN 5925-00-064-1155
NSN 7035-01-425-4496
NSN 5910-00-156-0993
NSN 5965-01-136-4781
NSN 5965-01-408-7260
NSN 6105-00-072-6664
NSN 6145-01-365-7801