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 6685-01-419-0752
NSN 5950-00-799-2566
NSN 5965-01-103-5133
NSN 6650-00-449-6983
NSN 5975-01-433-1612
NSN 6150-01-502-7774
NSN 6220-01-326-5432
NSN 5930-01-466-0101
NSN 5915-01-462-9178
NSN 5895-00-962-5564
NSN 2925-01-320-6512
NSN 5920-00-593-6496