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 6685-00-218-1229
NSN 6620-00-202-5122
NSN 5950-00-370-3187
NSN 6110-01-170-3566
NSN 5999-01-578-1686
NSN 5920-01-197-2570
NSN 5905-01-658-7356
NSN 6650-01-459-8703
NSN 5950-00-851-8161
NSN 5965-01-074-3083
NSN 5925-00-001-5977
NSN 6620-01-633-8443