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 6145-00-201-1330
NSN 5960-00-728-3459
NSN 5975-01-614-7533
NSN 5975-01-217-2516
NSN 4140-01-534-9987
NSN 6130-01-394-9406
NSN 6150-01-631-4027
NSN 5996-00-594-8587
NSN 5905-01-206-4640
NSN 6645-01-069-3286
NSN 5965-01-100-1195
NSN 5935-01-123-9933