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 6105-00-433-1574
NSN 5835-01-457-5630
NSN 6220-01-135-3841
NSN 5965-00-236-0016
NSN 5996-00-001-2773
NSN 5930-01-584-5286
NSN 5975-01-578-8319
NSN 5985-01-240-5388
NSN 5945-00-462-7408
NSN 6220-01-058-9107
NSN 5975-00-868-8772
NSN 5999-00-942-9927