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 5925-01-109-5868
NSN 5920-00-456-5211
NSN 6650-01-075-6438
NSN 6320-01-021-6633
NSN 5935-01-341-6466
NSN 6105-00-862-4951
NSN 5996-01-020-5759
NSN 2925-00-684-7708
NSN 5905-00-348-6757
NSN 5915-01-359-4847
NSN 6220-01-144-5166
NSN 6650-00-514-3531