Two different shapes of nut are used for this application.
No other part numbers with same form, fit, and function found.
NSN 5999-01-259-8595
NSN 6110-01-027-0656
NSN 6240-01-165-2693
NSN 6105-01-615-8060
NSN 5996-01-384-5521
NSN 6620-01-436-2715
NSN 6145-01-121-4371
NSN 6620-00-159-0866
NSN 5915-00-287-5062
NSN 5895-01-074-7902
NSN 6650-01-235-7555
NSN 6145-00-969-5612