I ran into a problem with applying the LED strips to the hat. In my mind I assumed it would be easy to align the rows of LEDs because the strips should be uniformed. That assumption is wrong on two accounts. First, the hat itself is not a perfect cylinder, so the top row and bottom row have quite a difference in circumference. The 5 meter strip is also not precicesly uniformed. That's because the flexible PCB material actually comes in 1/2 meter lengths. Each time two lengths meet up there is a variance in the distance between the first and last LED on the mating strips.