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 6645-00-155-2398
NSN 6110-01-278-9376
NSN 6150-01-467-2147
NSN 6650-01-129-8343
NSN 7035-00-020-2227
NSN 5895-01-444-5088
NSN 6135-00-756-6149
NSN 5985-01-417-5672
NSN 6150-01-097-9007
NSN 6130-00-070-6140
NSN 6110-01-020-8153
NSN 6610-01-593-0135