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 5990-01-463-2279
NSN 6610-00-222-4108
NSN 2925-00-816-8765
NSN 6650-01-090-2059
NSN 5950-01-200-7893
NSN 7035-00-413-0992
NSN 5950-01-084-6667
NSN 5935-01-126-2851
NSN 6645-00-269-2764
NSN 6150-00-576-3964
NSN 6320-01-036-2598
NSN 6645-00-246-4934