Combined protection, tested in categories D, C, B (EN 61643), specifically designed for RS485 and fieldbus applications such as Profibus DP. For use at the boundaries of LPZ 0 to protect against surges (typically at the point of cable entry) up to LPZ 3. Available as standard OVR RS485 format or compact OVR RS485Q and Slim Line OVR RS485 versions for installation.