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 5855-01-053-9684
NSN 5990-01-481-5274
NSN 6610-01-005-5832
NSN 6620-01-344-4005
NSN 5905-01-422-4778
NSN 5985-01-353-9644
NSN 6610-00-913-7069
NSN 5960-01-541-5734
NSN 2925-01-567-8027
NSN 5975-01-318-3074
NSN 6320-01-228-2380
NSN 6685-01-571-2462