Yes, definitely don't send power down the wrong way, you could blow all the pixels. Check the wires on the edge, it should have a white dot on it to show positive? Best thing to do is cut off a single pixel and plug it into your controller on test mode to see if it is the right way around. Maybe take a picture if you want guidance, but there should be a white piece of paper showing the orientation or a photo in the ali listing.Hi Mark, all of my lights have arrived, but I do not know which end of the 1000count pixels I need to send the data into? I cannot see any markings at all. I didn't want to send the data in the wrong way, in case it causes more damage than good. Thanks