Geyer Electronic is an electronics manufacturer and supplier based in Germany that specializes in power supplies, portable medical equipment, connected medical devices, signal conditioning, and robots. 12.89997 is a battery charger that is designed to be used in portable medical equipment and other connected medical devices. It is designed to be as lightweight and efficient as possible, while providing reliable, safe power to all connected equipment. Its features include a wide input voltage range, overvoltage protection, and built-in temperature monitoring.