A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5945-01-584-8799
NSN 5930-00-241-8706
NSN 5998-00-541-8792
NSN 6320-01-456-2022
NSN 6110-01-519-5353
NSN 6135-01-333-6737
NSN 6645-01-454-2726
NSN 6620-01-382-7392
NSN 6620-01-659-1256
NSN 5945-00-735-0827
NSN 2925-00-446-2447
NSN 5925-00-192-4363