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 5920-01-645-4348
NSN 6685-01-604-8958
NSN 6320-01-512-2031
NSN 5920-01-514-4095
NSN 6645-01-246-2725
NSN 6620-01-032-3937
NSN 6105-00-607-3297
NSN 6150-00-024-2505
NSN 5945-01-194-7723
NSN 5920-00-594-3124
NSN 5935-01-459-3545
NSN 6105-01-474-7891