EV4-Series Waterproof RGBW Amplifier -5A/CHWaterproof RGBW (RED, GREEN, BLUE, WHITE) Amplifier can be used with any of our RGB LED Controllers to extend the number of the RGB LED Light Strips or Bars connected to it. RGB Amplifiers are required if exceeding the maximum load capacity of the RGB controller. Increases the load capability and extends the signal of the universal RGB controllers. To simplify, the RGBW controller (sold separately) is the brain. It creates the program, function, and