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 5925-01-165-7053
NSN 5960-01-495-0859
NSN 5920-01-312-4452
NSN 5950-01-128-0510
NSN 5895-00-987-3633
NSN 5945-00-587-4702
NSN 5975-00-153-0050
NSN 4140-01-487-7425
NSN 5905-00-678-5320
NSN 5985-00-158-3204
NSN 6620-01-429-9115
NSN 5915-01-461-8132