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 6685-01-100-1071
NSN 5920-01-062-2994
NSN 5930-01-425-3276
NSN 5895-00-176-1776
NSN 5990-01-188-7309
NSN 6110-00-058-6732
NSN 6685-01-606-1660
NSN 5835-01-615-8864
NSN 5930-01-354-7262
NSN 5905-01-284-5189
NSN 5895-01-534-2173
NSN 5910-01-618-6407