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 2925-01-239-6044
NSN 6610-00-149-1534
NSN 5895-01-606-8766
NSN 7035-01-322-8180
NSN 6650-00-389-4111
NSN 6105-01-560-2043
NSN 5985-00-838-3851
NSN 5985-00-270-8456
NSN 5960-01-531-9108
NSN 5895-00-833-1525
NSN 6620-00-450-9995
NSN 6240-01-500-2152