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 5915-01-142-8641
NSN 5925-01-503-6177
NSN 5950-00-679-0524
NSN 5950-00-061-2235
NSN 6650-01-192-9075
NSN 5975-00-478-2126
NSN 6105-01-244-3254
NSN 5950-01-621-9714
NSN 2925-00-455-2367
NSN 6650-00-052-3202
NSN 7035-01-411-6062
NSN 5965-00-004-6371