The MM3Z24VT1G is a voltage suppressor from ON Semiconductor. It is a 600W surface mount device made of a Zener diode and a transistor. It is rated for a peak pulse power of 600W, a reverse breakdown voltage of 24V, and a peak clamping voltage of 28.1V. The device is typically used to protect sensitive components from overvoltage transients, ESD, and other high-voltage events.