This unit shows an error when plugged in. No batteries. sold as is for parts. The Monster Power HTUPS 2700 Home Theater Surge Protection unit is a high-quality power protection device designed to safeguard your home theater system from power surges and spikes. Made by the trusted brand Monster Power, this unit is a reliable choice to ensure the longevity of your electronics. With its surge protection capabilities, this unit provides peace of mind for your valuable home entertainment equipment.