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 6220-00-218-0857
NSN 5996-00-626-3766
NSN 6110-00-466-1674
NSN 6320-01-067-0474
NSN 7035-01-115-8996
NSN 6130-00-186-8460
NSN 5990-00-600-6151
NSN 6610-01-102-2256
NSN 5999-00-931-2385
NSN 7035-01-008-4680
NSN 7035-01-529-0126
NSN 5905-01-382-9671