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 6110-01-158-6138
NSN 5950-01-296-7567
NSN 5905-01-646-5503
NSN 5999-00-422-8491
NSN 7035-01-398-9581
NSN 6650-00-190-5158
NSN 6620-01-438-0415
NSN 6145-01-423-8470
NSN 6650-01-633-0333
NSN 6320-01-576-6310
NSN 6650-01-641-5356
NSN 5935-01-205-1909