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 5975-01-158-1061
NSN 6220-00-587-4891
NSN 5920-01-550-4585
NSN 6105-00-110-5861
NSN 7035-00-003-7518
NSN 5950-01-423-9123
NSN 2925-01-283-6740
NSN 6645-01-422-9672
NSN 5855-01-525-5251
NSN 5960-01-089-8155
NSN 5910-01-608-2402
NSN 5910-01-429-7818