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 4140-01-165-2663
NSN 5930-00-615-6334
NSN 5915-01-572-3225
NSN 4140-00-274-9638
NSN 6320-00-857-4073
NSN 5996-00-167-3531
NSN 5965-01-238-0488
NSN 6135-00-643-4843
NSN 6645-01-426-7652
NSN 6620-01-247-1816
NSN 5915-01-333-0098
NSN 5996-00-930-0150