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 5960-01-337-5339
NSN 2925-01-629-9416
NSN 6150-00-402-3077
NSN 6145-00-081-3993
NSN 2925-01-445-4095
NSN 6685-01-606-2802
NSN 6320-01-441-1371
NSN 2925-00-764-0167
NSN 5935-01-220-4272
NSN 6220-01-411-9454
NSN 5996-01-464-9791
NSN 5965-01-201-8399