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 7035-00-337-8745
NSN 5990-00-373-9787
NSN 5920-00-914-2707
NSN 6620-00-079-4615
NSN 6650-00-890-0480
NSN 6135-00-948-7061
NSN 5985-01-469-7399
NSN 5945-01-146-6694
NSN 6220-00-188-7525
NSN 5895-00-284-4835
NSN 6645-01-013-6254
NSN 4140-00-908-2763