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 6150-00-575-8961
NSN 5855-01-588-6065
NSN 5895-00-561-3326
NSN 7035-01-499-9239
NSN 6320-01-443-3826
NSN 5930-00-655-0776
NSN 5895-01-265-7236
NSN 5895-01-472-3672
NSN 5855-01-483-2774
NSN 5985-01-075-4699
NSN 5910-01-183-0897
NSN 6240-00-284-1457