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 5835-01-143-9143
NSN 5905-01-044-5606
NSN 4140-01-056-4453
NSN 5975-01-651-2778
NSN 6150-00-229-1407
NSN 5915-01-355-5777
NSN 5999-01-385-3514
NSN 6135-00-809-2148
NSN 5910-01-236-2560
NSN 6130-01-435-7169
NSN 5999-01-555-7511
NSN 6130-01-580-6485