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 5996-00-187-8072
NSN 6220-01-606-8226
NSN 5915-01-431-2321
NSN 5950-01-367-1870
NSN 6220-01-015-2956
NSN 5990-00-210-2953
NSN 5910-01-151-6513
NSN 5950-01-377-5790
NSN 5950-01-525-7896
NSN 5960-01-007-5838
NSN 5998-01-482-0903
NSN 5910-01-141-2049