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 5910-01-483-6282
NSN 6145-01-391-6199
NSN 6110-00-840-6560
NSN 5920-00-071-4878
NSN 7035-00-703-3535
NSN 5930-00-166-6793
NSN 5996-01-415-9202
NSN 6320-01-352-5653
NSN 5999-01-442-7643
NSN 5999-01-265-7037
NSN 5998-01-369-3808
NSN 6650-01-126-6238