The RV821K20_-HE from Stackpole Electronics is a Varistor with AC Voltage Rating 510 V, DC Voltage Rating 670 V, Clamping Voltage 1355 V, Capacitance 410 pF, Temperature Operating Range -40 to 85 Degree C. Tags: Through Hole. More details for RV821K20_-HE can be seen below.