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 5935-00-067-7493
NSN 5990-01-443-2931
NSN 6685-00-931-6744
NSN 6645-01-306-7376
NSN 5990-01-616-5242
NSN 5930-00-895-9203
NSN 5910-00-177-8291
NSN 5975-01-246-3114
NSN 5996-00-730-3963
NSN 6650-01-509-8018
NSN 6145-01-137-4473
NSN 6135-00-990-1822