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 6610-01-444-2050
NSN 6620-01-524-7562
NSN 6320-00-583-3104
NSN 6685-01-592-0709
NSN 5960-01-654-4353
NSN 6650-00-415-6349
NSN 6650-01-573-7165
NSN 5960-01-388-1988
NSN 5990-01-421-5342
NSN 6650-00-221-7119
NSN 5925-01-073-7034
NSN 6110-01-057-6445