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 5910-01-230-9966
NSN 6645-01-484-9847
NSN 6145-01-649-8002
NSN 4140-01-528-7182
NSN 5998-01-517-5420
NSN 5835-01-090-6712
NSN 5895-01-586-0913
NSN 5998-01-453-9989
NSN 7035-01-487-6481
NSN 6650-01-437-8852
NSN 5835-01-123-8305
NSN 6135-01-316-9794