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 5920-01-142-1836
NSN 4140-01-501-5631
NSN 5965-01-052-3765
NSN 5910-01-474-5479
NSN 5998-00-518-5118
NSN 6685-01-176-4905
NSN 5925-01-307-0693
NSN 5999-01-061-1360
NSN 5975-00-470-2320
NSN 6645-01-586-5278
NSN 6220-00-898-7311
NSN 5998-00-373-3142