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 5930-00-079-0171
NSN 6610-00-087-8096
NSN 5910-00-919-7127
NSN 5855-01-050-4944
NSN 6650-01-479-5386
NSN 5925-00-829-4897
NSN 6135-01-529-8523
NSN 5950-01-616-9588
NSN 6685-01-567-9140
NSN 6135-01-091-6021
NSN 4140-01-440-4379
NSN 6145-00-190-7489