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 7035-00-096-9986
NSN 6240-01-054-9171
NSN 5905-01-435-7327
NSN 6240-00-342-9756
NSN 5935-01-532-1509
NSN 5855-00-532-0025
NSN 6110-00-202-1021
NSN 6130-01-129-9243
NSN 5925-01-415-6551
NSN 6110-00-905-4858
NSN 6320-01-333-5782
NSN 5935-00-301-3710