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 5915-01-048-0106
NSN 6645-01-033-1171
NSN 6105-01-435-0825
NSN 6145-00-475-6909
NSN 6620-01-573-8003
NSN 5910-00-271-7588
NSN 6110-01-566-3973
NSN 5910-01-120-0291
NSN 5996-01-566-0344
NSN 6150-01-285-4580
NSN 5895-01-069-2479
NSN 5925-00-757-4981