The K4-PB is a cape for the PocketBeagle designed to drive WS2811 LED pixels. It has 4 local ports (fused with LED indicators) that can each drive over 700 pixels (with power injection) at 40FPS. It also has a 3pin UART header that can be used to drive a single DMX universe or for PixelNet/Renard/LOR. The K4-PB is very small and is designed to fit into a small TA-200 enclosure with a "nano style" USB WIFI adapter. The PocketBeagle is powered by the same power supply powering the pixels. There are jumpers on the board to select either 5V or 12V power. The jumpers are set from the factory to 12 volts. You should not need to change the jumpers unless you are using a 5 volt power supply.