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 5975-01-139-5135
NSN 5905-00-153-8464
NSN 5985-00-950-0249
NSN 6645-01-026-6659
NSN 6650-01-571-9386
NSN 6620-01-549-3559
NSN 2925-01-127-0167
NSN 5925-01-090-3859
NSN 6105-01-363-9002
NSN 6320-01-422-1212
NSN 5905-01-132-7971
NSN 6685-01-448-7164