Uniden BTHS500 Owner's Manual page 6

Use ONLY the power adapter supplied with the BTHS500! Using
any other adapter could damage your BTHS500, create a fire
hazard, or cause a risk of electric shock!
2) While charging the LED will light up red and when charging
is complete, the LED will turn off.
General Use;
For optimum charging turn power off before connecting charger.
After charging turn power on and BTHS500 will automatically
seek the previous connection.
If power is on when charger is connected then Bluetooth is
disconnected. After charge press the Multi-Function button
momentarily to seek the previous connection.
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