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 6220-01-422-1429
NSN 5996-01-207-0804
NSN 5998-01-192-5491
NSN 5990-01-548-5979
NSN 5855-00-930-9478
NSN 6150-00-901-7264
NSN 5990-01-292-6000
NSN 6130-01-594-7668
NSN 5925-00-736-0425
NSN 6320-00-925-0558
NSN 6150-01-534-8128
NSN 6110-01-528-6373