KSC2xy is a very flexible model. It has two colours to choose from. "xy" specifies colors. Default type is KSC2rb in Red and Blue; but you can specify other colors in orders using "xy". LEDs can be in stable 10-LEDs on for best signal strength, or flashing 4-LEDs on for long operation and better visual effect. With these flexible options, there are 5 operating modes available.