The Liown 271KD20 Varistor is a radial leaded, RoHS compliant electronic component rated at 455V, 1W, 127J, 225V, 1500pF at 1kHz, 175V, 270V, and 6.5kA. It is used in voltage circuit applications, particularly those that require surge protection, to limit the voltage and regulate currents. It is able to tolerate large spikes in voltage, allowing it to absorb high energy and protect the circuit from damage.