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 5998-00-617-9499
NSN 5950-01-441-6807
NSN 6105-01-364-8811
NSN 5998-00-149-0726
NSN 6620-00-223-2500
NSN 5950-01-281-5560
NSN 5920-01-006-9821
NSN 5990-00-130-7293
NSN 6135-00-862-5736
NSN 5910-00-630-6819
NSN 6220-00-731-3795
NSN 5975-01-303-4239