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 5985-00-953-1519
NSN 6650-00-563-3880
NSN 2925-00-149-0760
NSN 5910-01-503-4356
NSN 6610-00-910-6822
NSN 5855-01-054-9014
NSN 7035-01-024-9511
NSN 5835-01-091-8353
NSN 6110-00-632-6078
NSN 5920-01-622-6662
NSN 7035-00-104-7613
NSN 5905-00-467-8404