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 6650-01-172-9476
NSN 6240-01-210-4217
NSN 5998-01-660-2452
NSN 6150-01-430-7207
NSN 6130-00-397-7690
NSN 6650-00-862-2142
NSN 7035-01-374-0005
NSN 5930-01-287-1711
NSN 6105-01-076-5183
NSN 6685-01-371-3974
NSN 5990-01-166-2237
NSN 5905-01-102-9810