Working fine as described
Akari 4V 0.5Ah Sealed Lead Acid Rechargeable Battery For Mosquito Bat / Toys
The stick is too small
Description
The sensor tap system must have power, whether battery or a transformer. With electricity supply, the sensor can detect an object, like a hand opposite the basin tap. The solenoid valve opens when an obstruction is perceived. This way, water flows through the pipe and spout.