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 5985-00-678-0881
NSN 5960-01-622-0393
NSN 6685-00-596-8765
NSN 5905-00-123-4094
NSN 5855-01-007-9541
NSN 5930-01-211-5684
NSN 6685-01-048-9654
NSN 5985-01-034-9227
NSN 6110-01-438-4368
NSN 6150-00-511-8563
NSN 5935-01-433-2291
NSN 6610-00-994-0190