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 5920-00-584-4592
NSN 7035-01-332-3496
NSN 6650-00-930-3372
NSN 2925-01-016-0876
NSN 6685-00-402-2458
NSN 5950-00-920-8538
NSN 6320-00-036-3688
NSN 6110-00-635-6023
NSN 5950-01-463-9075
NSN 5910-01-069-2557
NSN 5930-00-081-2238
NSN 6130-00-186-8460