The 820KD07J is a radial leaded Metal Oxide Varistor (MOV) manufactured by Yageo. It has a surge current rating of 5kA @8/20 µS, voltage rating of 280VAC, and a maximum allowable power dissipation of 500mW. It has a 6mm disk diameter and is RoHS compliant. The main feature of this part is its ability to stabilize and protect electronic circuits from dangerous voltage transients and surges. It is often used in electrical panels, appliances, motor control, LED lighting, and other applications.