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 5996-01-359-4222
NSN 5920-01-050-5565
NSN 6645-00-072-9243
NSN 6220-00-239-9219
NSN 5945-01-078-2385
NSN 5855-01-328-3570
NSN 4140-01-447-3141
NSN 6620-01-361-8685
NSN 5895-01-634-0630
NSN 5835-01-442-6079
NSN 6645-01-578-6815
NSN 5975-00-134-3667