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 2925-01-420-2362
NSN 5965-01-298-6313
NSN 6105-01-594-2251
NSN 5930-00-679-9942
NSN 5895-00-081-3293
NSN 6150-01-139-6759
NSN 6240-01-380-2127
NSN 5895-01-545-6718
NSN 5985-01-377-0137
NSN 5990-00-140-0109
NSN 6150-01-525-6945
NSN 6145-01-111-2876