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 5905-00-270-4331
NSN 6240-01-323-5386
NSN 7035-00-543-3272
NSN 6145-00-730-3933
NSN 4140-01-390-9552
NSN 6105-00-922-8597
NSN 7035-01-452-9086
NSN 5915-01-094-5681
NSN 6620-01-606-8964
NSN 5915-01-241-3712
NSN 5895-01-446-9656
NSN 5855-01-606-3745