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 5996-01-207-9107
NSN 5950-01-479-3792
NSN 5925-00-518-9744
NSN 5999-01-512-9178
NSN 5910-01-108-3766
NSN 6105-01-026-4749
NSN 6685-01-249-1509
NSN 5835-01-198-2221
NSN 6150-01-444-4470
NSN 5855-01-366-2429
NSN 5965-01-311-3613
NSN 4140-01-629-6204