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 6105-01-105-3641
NSN 6650-01-481-6647
NSN 5985-00-649-7295
NSN 6150-00-132-0695
NSN 6130-01-373-1911
NSN 4140-01-364-0109
NSN 6685-00-401-4057
NSN 5895-01-074-2784
NSN 5975-01-101-5615
NSN 6150-01-158-5438
NSN 5996-01-512-0800
NSN 5985-00-407-2273