To protect consumer systems in the mains connection compartment of the meter cabinet on a 40 mm busbar against transient overvoltages caused by direct and indirect lightning strikes and switching operations. Meets all requirements for the installation of surge protection according to DIN0100-534, test classes I, II, III according to IEC 61643-1, SPD type T1+2+3, corresponds to IEC 61643-11: 2011, EN 61643 -11:2012+A11:2018, lightning protection class III and IV according to IEC 62305, leakage current-free, with integrated fuse to protect the SmartMeterGateway and the APZ