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 6650-00-161-4122
NSN 5996-01-654-6729
NSN 2925-00-983-7521
NSN 5915-01-506-3910
NSN 6220-01-302-2214
NSN 6110-01-342-4253
NSN 5998-00-631-1540
NSN 6135-01-077-3787
NSN 5965-00-539-7778
NSN 6150-01-170-4307
NSN 5950-01-394-2329
NSN 5920-01-267-9036