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 5925-00-964-9654
NSN 5920-01-534-1344
NSN 6145-00-261-8202
NSN 6320-01-039-5891
NSN 6220-01-140-9230
NSN 6320-00-025-9910
NSN 6105-01-275-7052
NSN 7035-00-421-8710
NSN 5915-00-690-1865
NSN 5915-01-471-7814
NSN 6645-01-457-0158
NSN 5855-00-832-9341