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 5835-00-957-3565
NSN 5905-01-323-5836
NSN 5950-00-927-8644
NSN 5985-01-630-9468
NSN 6320-01-612-7035
NSN 6645-00-204-4100
NSN 6320-00-139-1090
NSN 6650-00-095-6490
NSN 5910-01-534-7699
NSN 6320-01-359-3921
NSN 6610-01-256-7938
NSN 6685-01-608-2187