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 6685-01-536-8616
NSN 5998-00-948-5298
NSN 6145-01-048-2750
NSN 5975-00-269-4365
NSN 6685-00-148-8247
NSN 5895-01-141-7025
NSN 5996-01-106-2763
NSN 5915-00-007-9237
NSN 7035-01-080-3392
NSN 5999-00-902-3920
NSN 5965-01-432-1943
NSN 5895-00-376-5074