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 5925-01-421-5973
NSN 5999-01-322-8547
NSN 6620-00-098-5652
NSN 6610-00-671-6744
NSN 6685-01-631-4225
NSN 4140-00-886-1710
NSN 6610-01-153-8625
NSN 6645-00-819-5045
NSN 5945-00-066-7194
NSN 6650-01-050-8680
NSN 6685-01-458-2777
NSN 5990-00-717-3432