GTCA28-x-R03 High Voltage Series GDTs Littelfuse GTCA28-x-R03 High Voltage Series GDTs (ceramic gas discharge tubes) are commonly used to help protect high voltage circuits. They offer a high level of surge protection, low capacitance, and a broad array of break over voltage levels, making them suitable for applications such as branch circuits, medical electronics, and surge protection on power lines. With such features, Littelfuse GTCA28-x-R03 High Voltage Series GDTs can help equipment meet the most stringent regulatory standards.