So several years ago I order in some 350 THHN AL colors for a job. About 800 feet each white, black, red, blue. Vendor is Priority W&C. All goes fine. Fast forward to now, I am doing a few 320-400 amp services and need some short lengths, and have some of those colors left over so I dig them out to use. Im hooking up this one service and I notice that the white looks a little smaller. I check the printing and it definitly says 350 KCMIL. I get out the dial calipers and the conductor is about a hundred thousandths smallerthan the other colors, and corresponds to 250 KCMIL. Both are compact stranded so not confusion there. Someone must have mislabeled it at the factory. Fortunately it was the neutral, and I (meant to) use a full size, so its rally not an issue, but a pretty big screw up for a wire manufacturer. Imagine if it had been one of the phases?