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 5960-00-131-1218
NSN 2925-01-591-4030
NSN 5960-01-456-1735
NSN 6685-01-433-2050
NSN 5895-00-816-9763
NSN 5920-00-584-4592
NSN 5945-00-732-8532
NSN 5985-01-513-5982
NSN 6320-01-449-1014
NSN 6105-01-370-2573
NSN 6130-01-425-2340
NSN 5930-01-545-0747