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 5975-00-801-0638
NSN 6685-01-512-8345
NSN 6110-00-571-1749
NSN 5895-01-390-0212
NSN 5990-01-128-7599
NSN 5935-00-608-7673
NSN 5895-00-168-7648
NSN 5950-01-210-7282
NSN 5990-01-432-4249
NSN 6240-00-689-8504
NSN 5965-01-300-9663
NSN 7035-01-332-9582