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 6610-00-477-7931
NSN 4140-01-196-6331
NSN 6610-01-576-2802
NSN 5935-01-105-6178
NSN 2925-01-474-3363
NSN 5915-00-547-8018
NSN 5945-01-626-4693
NSN 5930-00-190-6997
NSN 6130-01-353-7282
NSN 6105-01-426-3882
NSN 5950-01-162-4938
NSN 5920-00-738-1131