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 5960-00-183-8016
NSN 6620-01-119-9239
NSN 5915-01-589-6951
NSN 2925-01-394-9658
NSN 5960-01-558-7787
NSN 5835-01-509-8992
NSN 5996-00-305-6152
NSN 5910-00-518-1477
NSN 5835-01-307-8954
NSN 6320-01-554-0901
NSN 4140-00-152-7092
NSN 6110-00-218-4737