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 5996-00-843-8768
NSN 6685-01-304-2122
NSN 6105-01-441-9312
NSN 5950-01-488-4891
NSN 5910-01-025-9987
NSN 6645-00-235-4685
NSN 5975-01-167-8598
NSN 5998-01-287-3267
NSN 5895-01-533-3752
NSN 5935-00-022-5792
NSN 6130-01-487-6366
NSN 5985-01-311-8848