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 5925-01-152-1931
NSN 6645-01-423-7760
NSN 6145-00-110-6619
NSN 6685-01-219-7959
NSN 6220-00-660-5539
NSN 6240-01-485-9452
NSN 5985-01-553-7912
NSN 5975-01-415-9450
NSN 5930-01-196-5954
NSN 5998-01-398-2170
NSN 7035-01-041-2754
NSN 5990-00-707-0731