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 6685-00-753-7429
NSN 6610-01-426-1011
NSN 4140-01-248-0157
NSN 5965-01-337-8411
NSN 5999-00-987-1534
NSN 5985-01-026-9810
NSN 5950-01-246-2479
NSN 6150-01-614-9851
NSN 6135-01-140-8201
NSN 7035-01-533-7421
NSN 6685-01-045-5002
NSN 4140-01-347-6503