The MVR40D78K-S from Meritek Electronics Corporation is a Varistor with AC Voltage Rating 485 V, DC Voltage Rating 640 V, Clamping Voltage 1290 V, Capacitance 3000 pF, Temperature Operating Range -40 to 105 Degree C. Tags: Through Hole. More details for MVR40D78K-S can be seen below.