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 6645-01-114-8044
NSN 6650-01-386-6711
NSN 6110-01-414-3500
NSN 5915-00-923-7186
NSN 5915-01-391-0659
NSN 5915-00-312-8011
NSN 5895-01-106-3312
NSN 7035-01-353-6861
NSN 5985-01-247-6950
NSN 5999-01-549-9664
NSN 6135-00-488-4478
NSN 5990-01-467-7575