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 6105-01-431-4201
NSN 5910-00-144-4383
NSN 6130-01-075-8469
NSN 5915-01-455-8577
NSN 6145-00-485-6812
NSN 6145-01-025-1822
NSN 6620-01-461-2387
NSN 5960-01-370-4285
NSN 6645-01-607-5999
NSN 6135-00-377-9165
NSN 5905-01-101-4440
NSN 6650-01-236-5916