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 2925-00-149-0760
NSN 6220-00-358-9580
NSN 5895-00-841-1745
NSN 6130-01-623-4297
NSN 6135-01-142-2417
NSN 7035-01-098-5474
NSN 4140-01-117-5698
NSN 6620-00-248-6950
NSN 6135-01-442-7275
NSN 6620-00-257-2783
NSN 6685-01-573-0366
NSN 5996-01-173-3202