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 5920-01-540-9624
NSN 5930-01-591-0607
NSN 5920-01-425-5700
NSN 6240-01-429-9826
NSN 6620-01-104-2699
NSN 5895-01-053-6273
NSN 6150-01-378-6736
NSN 5990-01-231-9608
NSN 5950-01-521-7950
NSN 5920-01-218-5415
NSN 2925-00-155-8091
NSN 5905-01-616-4892