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 5895-00-973-3852
NSN 5950-01-653-4800
NSN 5925-01-141-7586
NSN 6320-00-931-4855
NSN 6130-00-153-3136
NSN 5960-00-958-5222
NSN 5855-00-058-1293
NSN 6105-00-377-8206
NSN 6105-01-394-2603
NSN 5999-01-391-2532
NSN 5985-00-538-3790
NSN 5945-00-336-9360