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 5960-01-177-0338
NSN 6110-00-512-7845
NSN 5950-01-363-3356
NSN 5905-01-049-9115
NSN 5855-01-100-3272
NSN 5935-01-624-2193
NSN 5935-01-446-5817
NSN 6320-01-181-9474
NSN 6620-00-841-0346
NSN 6145-01-181-5936
NSN 5999-00-483-7470
NSN 5998-01-476-8693