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 2925-01-600-2309
NSN 6135-00-840-6451
NSN 5920-00-073-1528
NSN 5925-01-030-0482
NSN 5990-01-363-5728
NSN 5910-01-004-9285
NSN 5920-01-493-7051
NSN 5835-01-587-8787
NSN 5950-01-556-3064
NSN 6620-01-112-6440
NSN 6145-01-567-9671
NSN 5910-01-312-3931