The kit is supplied with three light-emitting diodes that connect directly to the JAB2 amplifier. The latter already has all the connectors to power those LEDs and is already configured to manage their behavior appropriately.
Similarly, the diodes are already wired, insulated and mounted on a screw with nut locking for easy mounting on your case.
A diode is used as voltage indicator, meaning that it lights up only when the unit is on.
A diode is used to charge indicator. That is to say, it lights to indicate that the battery of yourportable speaker is being charged. The reverse is also true, light off indicates that the charge cycle is complete.
Last diode serves as a Bluetooth pairing indicator. It lights up to confirm that the Bluetooth receiver amplifier is paired with your source (phone, tablet, computer ... etc.)