A nut having a sleeve portion on its under side, which can be crimped or clinched to hold the item in place when inserted in a hole.
NSN 5910-00-266-8438
NSN 6135-01-419-2233
NSN 5935-00-840-5806
NSN 5960-00-398-1029
NSN 6135-00-921-6487
NSN 5999-00-086-7296
NSN 5996-00-882-0791
NSN 6685-00-902-6773
NSN 6685-01-367-1125
NSN 5945-00-135-2299
NSN 6240-01-255-8961
NSN 5905-01-017-5129