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 5985-01-198-5146
NSN 6320-01-195-5583
NSN 6645-01-205-0549
NSN 5990-00-288-1820
NSN 6650-01-519-9165
NSN 5999-01-100-3665
NSN 6145-01-069-6982
NSN 5990-00-067-6791
NSN 6320-00-456-0836
NSN 6620-01-271-0711
NSN 6145-01-335-4944
NSN 5925-00-792-9073