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 5905-01-406-5654
NSN 5965-01-386-2988
NSN 5985-01-492-6257
NSN 5999-01-507-3150
NSN 6610-01-157-0426
NSN 5895-00-045-9695
NSN 5960-00-707-3335
NSN 5975-00-143-4658
NSN 5985-01-440-9350
NSN 5835-01-257-5342
NSN 6645-01-310-2949
NSN 5855-01-020-7982