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 6130-01-592-2961
NSN 5905-01-254-2741
NSN 6220-01-273-6024
NSN 5935-01-467-6118
NSN 6620-01-444-4048
NSN 6650-01-519-9165
NSN 5960-00-764-2564
NSN 5935-01-190-9167
NSN 5855-01-264-8599
NSN 6150-00-482-1128
NSN 5965-01-026-1125
NSN 5930-00-397-4164