A nut having an externally splined sleeve which holds it in position when forced into a hole of slightly smaller diameter.
NSN 5910-01-219-9043
NSN 6145-00-596-2606
NSN 6145-01-389-9447
NSN 5935-01-100-5906
NSN 5999-00-273-3995
NSN 5935-01-081-0955
NSN 6650-01-290-1029
NSN 5996-01-260-7371
NSN 5910-01-623-6754
NSN 5965-00-356-3838
NSN 6240-01-501-8865
NSN 6220-01-621-7604