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 5930-01-353-3068
NSN 5935-01-093-7347
NSN 5998-00-469-9554
NSN 6150-01-501-3340
NSN 6620-01-649-9948
NSN 5950-01-481-9133
NSN 6240-01-286-8275
NSN 5999-01-347-0195
NSN 5945-00-830-2809
NSN 5905-01-396-6938
NSN 5996-00-729-1250
NSN 5895-01-051-7613