The RGB LED can emit different colors by mixing the 3 basic colors red, green and blue. So it actually consists of 3 separate LEDs red, green and blue packed in a single case. That’s why it has 4 leads, one lead for each of the 3 colors and one common cathode or anode depending of the RGB LED type
LED: 10mm Common Cathode (CC)
Color: RGB
Voltage: 5V
Input: Digital Volt
Forward Voltage (RGB): (1.80, 2.0, 2.3)V
Max Forward Current (RGB): (20, 20, 20)mA