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 6150-01-250-6451
NSN 7035-01-469-0109
NSN 5920-01-329-6224
NSN 6320-00-646-3311
NSN 5985-01-317-5101
NSN 5998-00-150-2751
NSN 5975-01-451-2991
NSN 5935-00-197-9463
NSN 5855-01-154-3871
NSN 6685-01-568-3812
NSN 6610-00-226-4710
NSN 5975-01-055-6866