The SUNTREE SUP1-40 AC SPD 275V 2P 20-40KA is a Surge Protective Device (SPD) for AC electrical systems, designed to protect electrical and electronic equipment from damage caused by voltage surges such as lightning strikes or sudden voltage changes in the electrical system. This device is used for electrical systems with a voltage of 275V, has 2 poles (phase and neutral), and can handle surge currents of 20-40KA. It is suitable for installation in residential, commercial building electrical systems, and solar power systems.