The MSC040SMA120J from Microchip Technology is a MOSFET with Continous Drain Current 53 A, Drain Source Resistance 40 to 50 milliohm, Drain Source Breakdown Voltage 1200 V, Gate Source Voltage -10 to 25 V, Gate Source Threshold Voltage 1.8 to 2.8 V. Tags: Screw Mount. More details for MSC040SMA120J can be seen below.