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 5999-01-290-4777
NSN 6150-01-534-7757
NSN 5920-00-469-2648
NSN 5915-01-246-4664
NSN 6110-01-439-5212
NSN 2925-00-720-3948
NSN 6650-00-552-8377
NSN 6240-00-813-6328
NSN 6650-01-516-3631
NSN 6620-01-560-6933
NSN 5945-01-358-1383
NSN 6130-01-453-8262