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 5935-00-737-1268
NSN 5895-00-365-4813
NSN 6685-01-647-1285
NSN 6645-01-031-6402
NSN 5910-01-025-5408
NSN 6135-00-334-4500
NSN 5910-00-375-5045
NSN 5895-00-936-5510
NSN 5835-00-191-4793
NSN 7035-01-218-6960
NSN 5935-00-316-9410
NSN 6145-00-528-6467