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 4140-01-533-0611
NSN 5985-00-665-3998
NSN 5990-01-633-9503
NSN 5990-00-116-6590
NSN 5996-01-113-0377
NSN 6145-01-119-9040
NSN 6110-00-960-7341
NSN 5945-01-147-5377
NSN 5998-00-775-2693
NSN 6110-00-880-6376
NSN 5996-01-441-7910
NSN 7035-01-090-3369