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 5999-01-415-7089
NSN 5985-00-003-7416
NSN 5965-00-485-9575
NSN 5960-01-025-9388
NSN 5930-01-417-3148
NSN 6645-01-409-2003
NSN 6145-00-590-8642
NSN 2925-00-450-7783
NSN 7035-00-535-8109
NSN 6620-01-189-8153
NSN 4140-01-475-4270
NSN 6645-01-578-6815