5K has four buttons and two LEDs. The volume buttons are with Red LED, and multi-functional buttons are with Blue LED. You can easily recognize and distinguish the left and the right buttons by check the LED color.

Volume Buttons & Red LED

Multi-Functional Buttons & Blue LED

One of the Blue buttons has a small bump on it. It would help you to distinguish the buttons.

*Please note that the LED intensity is not uniform around the entire button area, and may not be bright enough at daylight.