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 5915-00-180-3979
NSN 5920-01-309-9216
NSN 5945-01-217-8690
NSN 6220-01-546-2064
NSN 5920-00-676-9113
NSN 5950-01-525-8127
NSN 6220-01-628-4370
NSN 7035-01-027-2259
NSN 5950-01-440-1197
NSN 6105-01-306-7151
NSN 5985-01-564-6857
NSN 5895-00-250-8931