The Pyronix BATT-ES1 3V Lithium Alarm Battery is a genuine Pyronix Deltabell Battery designed for home security systems. It comes in a vibrant orange colour and is wireless, making it easy to install. The battery is included with the purchase of the alarm, providing convenience for customers. With a power source of 3V, this battery is suitable for outdoor use and is a reliable choice for ensuring the functionality of home security systems.