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 5855-01-125-9167
NSN 5920-00-130-3593
NSN 5950-00-084-2919
NSN 6650-00-009-1427
NSN 6650-01-648-3903
NSN 5950-01-525-6374
NSN 5960-01-505-2426
NSN 6110-01-038-2028
NSN 5950-01-395-9852
NSN 5975-01-408-6601
NSN 5835-00-489-9569
NSN 6110-01-467-2882