Abstract: A surge protection device for protecting an electric power system from excessive voltage surges, including those caused by direct lightning strikes. Metal oxide varistors are wired between each incoming 115 volt power line and ground and between the two power lines. The varistors connect with the power lines on the user side of the main circuit breakers. The varistors are normally nonconductive but become conductive when excessive voltages are present on the power lines. Then, short circuits are established through the varistors to protect downline equipment. The varistors are embedded in a pliable filler material which fills a rigid polymeric shell. In the event of a direct lightning strike, the surge protector is destroyed sacrificially and the pressure resulting from the failure is relieved through the opposite ends of the shell.