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 5920-00-880-6581
NSN 6240-00-989-4398
NSN 5925-01-557-3098
NSN 5920-01-546-0705
NSN 5945-01-153-0268
NSN 5945-01-444-2611
NSN 5915-00-942-1125
NSN 6620-01-578-7561
NSN 6110-01-431-9836
NSN 5895-00-020-3398
NSN 5905-01-257-0504
NSN 5835-01-174-7700