Noark surge arresters are used to protect electrical installations against direct low-intensity lightning strikes. The line of surge arresters consists of class 1+2 devices. Suitable for lightning protection zone LPL III, IV according to EN 62305 in a 3-phase TN-C network, where the total surge current introduced into the electrical installation is 37.5 kA, and its surge can be 75 or 100 kA depending on the configuration and location of the point grounding, grounding of the lightning protection system and the place where the surge arrester is installed. The design of the Ex9UE1+2 12.5 surge arresters is based on varistor elements. It provides a low response time and meets the criteria of both Class I and II. Modular design with replaceable insert allows for quick and easy replacement of functional modules in the event of burnout due to frequent surge peaks