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 6620-01-561-6853
NSN 6105-00-565-5917
NSN 6105-01-581-5495
NSN 5998-00-500-3477
NSN 6150-01-408-8228
NSN 6320-01-304-3639
NSN 6645-00-221-7071
NSN 5996-01-246-4675
NSN 6320-01-170-4068
NSN 5990-01-177-2838
NSN 5855-00-688-9954
NSN 5910-01-424-0225