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 5925-00-269-2685
NSN 6320-01-116-3980
NSN 4140-00-299-6328
NSN 6645-01-149-2247
NSN 5930-01-413-9506
NSN 6150-01-076-4811
NSN 2925-00-922-8953
NSN 6620-01-431-9176
NSN 5915-01-626-2173
NSN 5960-01-579-9493
NSN 5950-01-381-2994
NSN 5920-01-376-4422