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 5930-00-735-4252
NSN 6135-01-390-1841
NSN 6130-01-307-6004
NSN 4140-00-307-2732
NSN 6240-00-244-0483
NSN 5999-01-305-1835
NSN 6685-01-541-4932
NSN 5996-00-004-4699
NSN 6650-01-502-6761
NSN 6135-00-927-5848
NSN 5925-01-560-0155
NSN 5960-01-210-8779