The Alarm.com ADC-VDBA-PM is a 16V, 1.25 Ah wall power supply kit designed for the Alarm.com ADC-VDB770 video doorbell cameras. Simply, plug-in the ADC-VDBA-PM power supply into a wall outlet for power. Then, run the power wires from the ADC-VDBA-PM to the VDB770 video doorbell using the included 10 Watt, 10 Ohm resistor.