As with most of these Revain cables, the polarity of the barrel connector has been reversed from what was listed at the time of purchase. It seems that the list has since been corrected. Instead of sending it back I just cut off the end of the stem and spliced it together to get the polarity right. As far as I can tell, it didn't hurt when wrong, but be aware of that before using it. Before use, check the specifications of your device to verify polarity.