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 5895-00-899-0334
NSN 5915-00-226-0910
NSN 2925-01-354-1752
NSN 2925-01-387-0870
NSN 5985-00-857-1426
NSN 5950-01-326-8508
NSN 5910-01-625-5332
NSN 5835-01-631-3940
NSN 6320-00-445-1187
NSN 5925-01-157-1289
NSN 6650-01-378-3270
NSN 4140-01-264-7466