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 5996-01-186-5671
NSN 5960-01-100-7381
NSN 5985-01-352-0972
NSN 5990-01-504-9265
NSN 6135-01-593-4212
NSN 6685-01-535-9332
NSN 5905-00-937-4418
NSN 5965-01-020-4104
NSN 6685-01-565-9049
NSN 6650-01-535-6287
NSN 5935-01-065-8448
NSN 5950-01-426-8810