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 6645-00-772-0532
NSN 6150-01-400-4211
NSN 5950-00-958-1559
NSN 5965-01-501-1106
NSN 5965-01-302-8522
NSN 6150-01-363-2798
NSN 5985-00-925-1216
NSN 5950-01-539-3240
NSN 5915-01-538-1753
NSN 5999-01-168-5852
NSN 6645-01-492-1055
NSN 5915-01-437-8801