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 6220-00-316-2500
NSN 5945-01-328-5654
NSN 6620-01-108-5824
NSN 5996-00-888-1180
NSN 2925-00-703-7522
NSN 5920-00-931-0752
NSN 5895-01-012-2202
NSN 5985-00-105-3774
NSN 6240-01-054-2289
NSN 5950-00-060-7183
NSN 5835-01-416-6455
NSN 2925-00-137-1209