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 5999-01-184-1774
NSN 6105-00-067-7517
NSN 6610-01-426-5090
NSN 6320-01-592-6248
NSN 6150-01-632-6623
NSN 5930-01-077-3954
NSN 5965-00-045-7156
NSN 5905-01-215-1546
NSN 2925-01-424-0235
NSN 5990-01-341-5735
NSN 6620-00-179-2575
NSN 6220-01-453-4975