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 5930-00-800-5359
NSN 5945-01-458-1277
NSN 5975-01-285-5772
NSN 5930-01-414-9260
NSN 5950-01-301-5816
NSN 6645-01-417-3279
NSN 6240-01-052-2488
NSN 5930-01-086-7602
NSN 5835-00-930-8500
NSN 5998-01-386-6271
NSN 6620-00-267-5273
NSN 5999-01-463-8641