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 6105-01-444-1201
NSN 5945-01-596-1297
NSN 6620-00-278-7313
NSN 5950-00-270-3063
NSN 5920-01-520-6954
NSN 6135-00-044-3860
NSN 5990-01-248-8222
NSN 5915-01-113-1576
NSN 6620-01-223-5998
NSN 5960-00-525-1898
NSN 5950-01-255-1879
NSN 5999-01-521-3919