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 6220-01-433-9502
NSN 6105-01-369-5457
NSN 4140-01-660-4143
NSN 5895-00-859-6421
NSN 6145-01-026-0030
NSN 5935-01-228-4789
NSN 5960-00-549-3760
NSN 6645-01-166-3788
NSN 6110-01-352-4891
NSN 6145-01-334-9523
NSN 6620-00-160-0844
NSN 5935-01-435-1857