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 5996-00-690-0705
NSN 2925-01-067-4446
NSN 6220-00-295-3594
NSN 5999-01-243-6994
NSN 5855-00-221-9435
NSN 6320-01-512-2031
NSN 5925-01-340-1185
NSN 6650-01-290-4001
NSN 6135-01-056-4609
NSN 5920-01-044-5621
NSN 5990-00-901-2574
NSN 2925-01-097-0903