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 5945-01-344-6823
NSN 6130-00-853-2309
NSN 5999-01-448-2813
NSN 6145-01-161-7392
NSN 6110-00-507-9040
NSN 5920-01-401-5315
NSN 6645-01-266-8831
NSN 6150-01-500-8474
NSN 5975-01-627-3922
NSN 5950-01-356-5706
NSN 5950-00-182-8204
NSN 5950-01-418-3641