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 5895-01-249-6701
NSN 6650-00-391-8404
NSN 5935-00-661-0825
NSN 5996-01-469-3140
NSN 6685-01-470-6827
NSN 2925-01-022-8332
NSN 6130-01-442-6052
NSN 5960-00-661-0477
NSN 5945-00-454-7407
NSN 5950-00-391-2458
NSN 5990-00-620-1137
NSN 6645-01-417-1913