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 5855-01-656-6808
NSN 6240-00-185-8367
NSN 6650-01-235-0981
NSN 6320-00-538-2132
NSN 4140-01-237-1509
NSN 6130-01-361-9268
NSN 5910-01-612-8158
NSN 5905-01-029-2213
NSN 5915-01-031-4599
NSN 6645-01-471-4960
NSN 6650-01-020-6148
NSN 5895-01-427-9856