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 6150-01-449-1040
NSN 5855-01-385-8846
NSN 5965-00-082-4087
NSN 5925-01-069-7607
NSN 6645-01-516-7978
NSN 5895-01-164-2218
NSN 5925-00-052-5874
NSN 6320-01-176-8367
NSN 6110-00-022-9565
NSN 6645-01-411-5657
NSN 5965-00-076-9561
NSN 5920-00-929-8095