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 5915-00-763-1197
NSN 5965-00-445-1843
NSN 5905-00-142-1807
NSN 2925-01-519-3221
NSN 6645-01-595-1160
NSN 6135-01-196-7399
NSN 6135-01-322-4655
NSN 5910-01-244-5276
NSN 5920-01-287-2759
NSN 6610-00-355-0450
NSN 5985-00-223-4235
NSN 5905-00-060-2757