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 6150-01-334-3774
NSN 5965-01-601-8507
NSN 6645-00-472-4048
NSN 6610-01-294-5666
NSN 5915-00-312-4398
NSN 6105-00-011-3671
NSN 6145-01-505-2180
NSN 6130-01-168-6219
NSN 5950-00-168-6297
NSN 5915-00-062-9409
NSN 5895-01-607-0906
NSN 5996-01-314-8613