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 5965-01-521-3224
NSN 6145-00-243-0583
NSN 5965-01-036-1325
NSN 5985-01-134-5252
NSN 5999-00-007-4167
NSN 6610-00-466-3104
NSN 5855-00-189-6066
NSN 5905-01-227-6380
NSN 6110-00-815-4686
NSN 6320-01-373-9355
NSN 5975-00-456-6003
NSN 5965-00-100-1291