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 2925-00-365-3289
NSN 6220-00-850-0365
NSN 6110-01-633-9660
NSN 5935-01-535-1173
NSN 5935-01-298-6004
NSN 5915-00-075-1086
NSN 6135-01-333-6737
NSN 5985-01-487-8805
NSN 6145-01-553-0589
NSN 5855-01-407-3739
NSN 2925-01-461-4347
NSN 6685-01-199-5304