Dual DC Power Smart Selection Switch - 2 Inputs to 1 Output

This Dual DC power smart selection switch has two input ports and one output port. Its output will select from one of two inputs: If Input A port has power, the output will always select Input A. If Input A port has no power, it will automatically switch to Input B port. When Input A port power comes back, it will automatically switch back to Input A ( if Input A is 12V or higher).
Features: Wide input range: 9V ~ 30V; Small size: 2.98 x 2.98 x 1.3 (74 x 74 x 32.5 mm); Light weight: 9.5 oz (269g ); Water resistant design.This Dual power smart selector input side has two 5.5 x 2.5mm Female connectors with 16AWG cables, output is a 5.5 x 2.5mm male barrel connector with 16AWG wires. It is very easy and flexible to connect with batteries and other power source.
You may use two batteries with one switch to provide twice running time. When one battery is out of power, it automatically switch to another battery. However, when switching between the two inputs, there will be a very short time period where there will be no output. You may not notice this interruption for many devices. If you are using it for a laptop computer or a tablet computer without an internal battery, it may shut down the computer or cause it to reboot.
You may also use this switch to configure a battery backup system for main power supply. When main power supply has no power, it will automatically switch to back up battery. When main power supply comes back, it will automatically switch back ( if Input A is 12V or higher).
Special Note: When switching between the two inputs, there will be a very short time period where there will be no output. You may not notice this interruption for many devices. However, if you are using it for a laptop computer or a tablet computer without an internal battery, it may shut down the computer or cause it to reboot.