These YU-Lite batteries are designed for use in Pyronix wireless alarm systems and in particular the alarm sounders including the Pyronix Deltabell-WE and Delta-MOD-WE. These 3.7v 4700mAh offer long lasting power and their low self discharge rate ensures an extremely long shelf life. Features Designed for use in Pyronix security systems and Deltabells High Capacity  Long shelf life Original Equipment Quality Available at wholesale trade prices Specifications Voltage 3.7V Capacity 4700mAh Chemistry Non-Rechargeable Lithium (LiMn02) Â