Rail-mounted device for installation on DIN-EN 60715 TH35 mounting rails. TÜV certified according to IEC 61643-11, certificate number: AN 50567910 0001. 4 division units = 72 mm wide. The modular combined surge protector reliably protects electrical systems from transient overvoltages. It offers high protection against direct lightning strikes in TT, TN-C, and TN-S systems. 12.5 kA surge current resistance per pole. Easy rail mounting and modular design enable quick installation and maintenance. Combines protection classes Type 1+2+3 in one device, providing comprehensive surge protection from the building entry to the end device. The use of a MUA-50 combined surge protector is mandatory according to DIN VDE 0100-443/534 for new buildings and expansions with high-power consumers (e.g., wall box, heat pump, PV system). If external lightning protection is present, a protection level is required: Type 1 in the main distribution (e.g., MUA-100, MUA-50) and Type 2 in the sub-distribution (e.g., MUA-30, MUA-20). A Type 2 surge protector in the sub-distribution is only required if the line length to the main distribution with installed Type 1+2+3 exceeds 10 meters.