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 6105-01-228-0112
NSN 5930-01-308-4202
NSN 6645-00-764-0412
NSN 5950-01-391-8020
NSN 6145-00-859-2522
NSN 6150-01-322-5386
NSN 5895-01-429-8160
NSN 6220-01-394-5263
NSN 6150-00-081-7216
NSN 6150-00-762-0956
NSN 7035-00-529-3128
NSN 5910-01-107-2305