Plastic mil-m-20693 or l-p-410
A nonmetallic unthreaded item generally round in cross-sectional shape which, when placed on/in a machined-out portion of the threads of a screw or bolt, or inserted into the machined-out portion of the threads of a nut, locks the item, to which it is fixed, to the attached mating member and prevents loosening during excessive vibration. Excludes bolt, self-locking; nut, self-locking (as modified); screw, self-locking; and insert, screw thread.
NSN 4140-01-360-0242
NSN 5930-01-218-4690
NSN 5925-01-443-5685
NSN 5975-01-514-0122
NSN 6320-01-347-2638
NSN 6610-01-541-0880
NSN 6240-01-394-5320
NSN 5915-01-065-9775
NSN 5975-00-171-3608
NSN 5910-00-779-9352
NSN 5996-00-081-0525
NSN 6645-01-137-3174