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 5990-01-065-0492
NSN 2925-01-354-1752
NSN 5990-01-548-5979
NSN 5905-00-279-4322
NSN 6220-01-038-1404
NSN 6320-01-082-2970
NSN 6645-00-456-2923
NSN 5950-01-005-0111
NSN 6110-01-249-1603
NSN 6645-01-224-0101
NSN 6130-00-925-2303
NSN 5985-01-323-7236