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 4140-01-288-7239
NSN 5960-01-100-5065
NSN 6650-01-379-1232
NSN 6320-01-195-5583
NSN 5998-01-239-1206
NSN 6240-00-145-1536
NSN 5895-01-160-8101
NSN 6150-01-381-3638
NSN 5998-00-181-3841
NSN 6130-01-424-7616
NSN 5975-01-620-2601
NSN 5950-01-556-1635