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 5905-01-250-2608
NSN 6105-00-044-3269
NSN 5915-01-354-0920
NSN 5895-01-551-0892
NSN 6650-00-759-8905
NSN 6220-00-528-7752
NSN 6645-01-099-2910
NSN 6650-01-168-8451
NSN
NSN 5835-01-552-8365
NSN 5895-01-436-2313
NSN 6610-01-371-3006