This battery box is for a standard AA battery, easy and cheap to get, and it includes an ON/OFF switch, too.
It has a 5.5mm DC barrel male connector on one side as output.
|Connector||5.5×2.1mm||5.5×2.5mm, 3.5×1.35mm etc|
|Wire Gauge||22AWG||20AWG, 24AWG etc|
|Length||5cm||According to the client’s requirements|