The Finder 7P.37.8.275.1003 is a single-phase Type 3 surge protection device for electrical safety applications. This surge arrester provides protection against voltage spikes in TN-S network configurations with a rated AC voltage of 230 V and a maximum continuous AC voltage of 275 V. It has a nominal discharge current (8/20) of 3 kA and offers protection levels of 1 kV for L-N and 1.5 kV for N-PE connections. The device utilizes varistor technology between L-N and a spark gap between N-PE for effective surge suppression. Made with a black plastic housing, this surge protection device is designed for installation in electrical distribution cabinets using 35 mm DIN rail mounting with a size of 1 TE. It accepts maximum conductor cross-sections of 6 mm² for rigid conductors and 4 mm² for flexible fine wire. The operating status is indicated by a front-facing LED display and status feedback via output contact in case of varistor failure. This surge protection device has EAC certification and is suitable for professional electrical installations that require reliable surge protection in single-phase systems. Its robust construction ensures long-term reliability under various operating conditions, while the precise protection characteristics safeguard electrical systems against transient overvoltages. The compact design allows for space-saving integration into existing distribution systems, and the clear status display facilitates maintenance and fault diagnosis. The device complies with relevant safety standards for electrical protection devices and offers a balanced combination of protection performance and practical installation convenience for demanding electrotechnical environments.