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 5835-01-054-2094
NSN 6110-01-141-7745
NSN 5975-00-003-5303
NSN 2925-01-376-9236
NSN 5998-01-529-7720
NSN 6105-01-024-9907
NSN 6320-01-081-7748
NSN 7035-01-062-1692
NSN 6620-01-470-6479
NSN 6150-00-821-5361
NSN 5930-00-909-8586
NSN 6650-01-452-8302