The item is a flight safety critical aircraft part (fscap)
A nut having 6 flat sides and an integral washer which extends beyond the flats or periphery. An integral feature is incorporated for locking on the threads of a mating member.
Classification: Nuts of iron or steel
NSN 6240-01-386-5952
NSN 4140-01-422-0439
NSN 5945-00-517-9566
NSN 5915-01-090-2480
NSN 6610-01-127-0724
NSN 5910-01-605-3393
NSN 6320-00-468-8421
NSN 6320-00-564-2772
NSN 5920-01-228-4384
NSN 6135-00-985-7845
NSN 6110-01-258-4300
NSN 5999-00-336-3237