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 5930-00-417-4497
NSN 5950-01-474-6085
NSN 5985-01-211-6549
NSN 6240-01-209-1972
NSN 6685-01-413-4632
NSN 5999-01-504-4250
NSN 5975-01-401-5355
NSN 5950-01-394-5352
NSN 5945-01-429-8942
NSN 5999-01-202-8191
NSN 6645-01-592-2557
NSN 2925-01-519-1247