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 2925-00-679-8131
NSN 5835-00-368-4182
NSN 6150-01-222-0667
NSN 5965-01-349-9029
NSN 6135-01-370-9440
NSN 6130-01-294-6382
NSN 5998-00-205-4138
NSN 5855-01-085-5354
NSN 5996-01-146-4202
NSN 5996-01-425-4228
NSN 5910-01-505-0086
NSN 6220-01-363-9713