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 6620-01-063-1441
NSN 6620-01-442-7951
NSN 6650-01-242-6155
NSN 5895-01-498-7875
NSN 6130-01-013-9343
NSN 5960-01-111-9918
NSN 5945-00-341-0558
NSN 5965-00-529-0602
NSN 5920-01-316-6504
NSN 4140-00-407-1326
NSN 5905-00-255-5695
NSN 5905-00-119-6932