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 6135-01-369-0939
NSN 6610-01-065-6057
NSN 5996-00-084-1790
NSN 5985-00-211-7383
NSN 6620-00-940-9292
NSN 6135-00-782-0930
NSN 5965-01-032-0940
NSN 4140-01-624-0444
NSN 6610-01-421-8703
NSN 6240-01-034-9457
NSN 5999-00-932-3690
NSN 6105-01-658-8011