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 6110-01-554-0260
NSN 5835-01-200-7153
NSN 5975-01-332-3464
NSN 6620-00-186-8220
NSN 6105-01-503-6826
NSN 5996-00-762-5899
NSN 6320-00-336-9123
NSN 5945-01-139-5179
NSN 5985-00-205-2922
NSN 7035-01-527-3883
NSN 5915-00-989-9172
NSN 5930-01-171-0905