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 6135-01-480-5560
NSN 6320-01-449-1014
NSN 5960-01-243-0007
NSN 6620-00-852-8245
NSN 6650-00-269-5000
NSN 6320-00-908-6841
NSN 5990-01-364-0813
NSN 5996-01-400-0917
NSN 5950-01-660-0241
NSN 5999-00-174-0099
NSN 5945-00-974-6783
NSN 5895-01-044-5425