Mersen, STPT12 Surge Protection Device 275 V ac Maximum Voltage Rating 25kA Maximum Surge Current Type 1 Arrester, Type

STP T12 12.5 is the series of combined Type 1+2/Class I+II devices for discharging lightning currents and protecting against voltage surges. Suitable as the first step of protection in incoming power supply panels and areas with exposure to the atmosphere, where installations are usually provided with an external lightning protection system.