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 5945-00-051-5437
NSN 6645-00-456-7653
NSN 5998-01-561-8765
NSN 6685-00-595-5376
NSN 6145-00-067-7436
NSN 6130-01-051-1405
NSN 6650-01-064-4975
NSN 5855-01-555-3354
NSN 7035-01-381-7622
NSN 5915-01-587-7295
NSN 6220-01-529-6728
NSN 6220-01-554-4186