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 7035-01-536-2255
NSN 6110-01-363-8818
NSN 5855-01-555-3354
NSN 6135-01-622-1296
NSN 5905-01-160-0044
NSN 6650-01-032-1786
NSN 6150-01-128-3227
NSN 5985-00-529-0093
NSN 5945-01-570-4730
NSN 5975-01-572-6295
NSN 5960-01-250-1095
NSN 6645-00-641-3202