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 6650-01-145-5173
NSN 6130-01-387-9748
NSN 5920-01-424-0745
NSN 5930-00-578-6967
NSN 6620-01-415-5803
NSN 6150-01-019-5734
NSN 6110-01-480-2544
NSN 5950-01-101-8205
NSN 6620-00-862-5567
NSN 6620-00-837-9484
NSN 5910-01-467-6569
NSN 6645-01-289-2950