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 2925-01-327-3069
NSN 6650-01-084-9726
NSN 6130-00-403-1301
NSN 6110-01-391-9254
NSN 5996-01-349-6783
NSN 4140-00-071-2209
NSN 6110-01-168-8600
NSN 6650-00-168-1502
NSN 5985-00-059-9386
NSN 6650-01-508-3651
NSN 5835-01-279-9508
NSN 5975-01-152-2521