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 6240-01-089-6149
NSN 6645-01-650-5735
NSN 5925-00-820-6415
NSN 6145-01-168-1070
NSN 5920-01-085-5490
NSN 5915-01-337-3230
NSN 6650-01-473-1355
NSN 6105-01-466-9090
NSN 5985-00-959-2901
NSN 5960-01-301-3315
NSN 5996-01-550-8867
NSN 6645-00-144-4868