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 6240-00-952-4501
NSN 6685-01-437-6426
NSN 5960-01-170-4057
NSN 5950-01-366-9973
NSN 6620-00-650-4452
NSN 5990-01-025-7466
NSN 6320-01-449-1014
NSN 6610-00-007-6832
NSN 7035-00-088-7355
NSN 2925-00-373-8837
NSN 6110-01-356-8245
NSN 5920-01-195-7563