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 6220-01-095-4860
NSN 6650-00-299-9681
NSN 6110-00-225-9021
NSN 6150-00-292-8778
NSN 6220-00-269-9942
NSN 5945-00-476-7100
NSN 5925-01-294-0379
NSN 6110-00-294-4067
NSN 5905-01-600-0179
NSN 4140-01-386-1447
NSN 5925-00-007-3962
NSN 5835-00-789-1454