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 6135-00-334-4500
NSN 5960-00-506-8064
NSN 6135-01-277-3345
NSN 5996-00-059-2407
NSN 6130-01-354-6401
NSN 5998-01-352-5411
NSN 6645-00-540-8930
NSN 6620-01-371-5040
NSN 2925-01-065-0060
NSN 5945-00-070-6203
NSN 6135-00-145-8884
NSN 6130-00-576-4867