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 5935-01-492-2918
NSN 6685-00-828-3438
NSN 5999-00-786-9623
NSN 5905-01-200-2052
NSN 6145-01-290-7163
NSN 6110-00-759-8317
NSN 6135-01-426-8282
NSN 6685-01-162-8829
NSN 5920-00-723-4554
NSN 6685-01-607-6481
NSN 5965-01-478-7329
NSN 5996-01-555-1120