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 5996-00-067-3652
NSN 5950-00-222-1413
NSN 5920-01-469-6025
NSN 5999-01-467-6318
NSN 6145-01-391-5148
NSN 5950-01-029-2994
NSN 6620-00-417-6285
NSN 5975-00-991-2385
NSN 5905-00-329-4178
NSN 6110-01-463-5624
NSN 6130-01-626-8365
NSN 5960-01-461-1384