A nut having an externally splined sleeve which holds it in position when forced into a hole of slightly smaller diameter.
NSN 5905-00-853-6527
NSN 5895-01-472-1996
NSN 5905-00-279-6374
NSN 5999-00-499-8949
NSN 5910-01-331-6992
NSN 5930-00-718-3850
NSN 5996-01-243-4072
NSN 6110-01-561-1408
NSN 6105-00-682-3866
NSN 6645-01-160-7707
NSN 5975-00-111-1226
NSN 5930-00-892-1668