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 5920-01-284-7306
NSN 6645-01-265-8729
NSN 5975-01-378-6917
NSN 5935-00-905-4810
NSN 5990-01-310-5630
NSN 5905-00-833-9534
NSN 5895-01-263-5123
NSN 6135-00-080-9176
NSN 5915-01-448-3510
NSN 5895-00-379-4699
NSN 5965-01-556-4337
NSN 5895-00-813-9883