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 5985-00-553-0349
NSN 7035-01-398-3494
NSN 5999-01-197-9539
NSN 6110-01-181-2762
NSN 6320-01-170-4068
NSN 4140-01-406-8169
NSN 6645-01-565-6973
NSN 5996-00-420-1408
NSN 5855-01-281-9700
NSN 5996-00-338-9760
NSN 5990-00-189-6649
NSN 5935-01-097-3661