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 5945-00-778-2837
NSN 6645-00-310-5839
NSN 5999-01-371-0381
NSN 6620-01-580-0883
NSN 5950-01-183-2849
NSN 5925-01-199-6033
NSN 5950-00-266-9058
NSN 5998-01-548-9156
NSN 5895-00-505-3749
NSN 5895-01-509-6221
NSN 5990-01-646-8048
NSN 6130-01-441-2241