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 6620-00-439-2442
NSN 5925-00-297-8821
NSN 5935-00-266-8506
NSN 5910-00-443-9319
NSN 5855-01-222-6065
NSN 6650-00-707-1417
NSN 5915-00-833-9025
NSN 6685-00-953-5449
NSN 6130-01-311-0175
NSN 6685-01-602-3572
NSN 5990-00-682-3531
NSN 5895-00-887-0552