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 5975-01-187-5403
NSN 6150-01-502-6709
NSN 5996-00-788-1218
NSN 6645-01-239-4619
NSN 5925-01-472-3382
NSN 5835-00-233-6327
NSN 6650-01-110-2142
NSN 5920-00-936-3952
NSN 5945-00-990-8366
NSN 5910-01-482-8782
NSN 5855-01-167-2162
NSN 6130-00-313-8292