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 5996-01-333-6644
NSN 5910-01-398-8829
NSN 6240-01-074-6550
NSN 5996-01-056-4952
NSN 6320-01-519-8767
NSN 6110-01-053-9432
NSN 6145-00-401-3518
NSN 6320-01-459-6992
NSN 6220-01-442-6733
NSN 5855-00-951-6483
NSN 2925-01-633-4048
NSN 5895-00-135-5622