The SSM3J331R from Toshiba is a MOSFET with Continous Drain Current -4 A, Drain Source Resistance 46 to 150 Milliohm, Drain Source Breakdown Voltage -20 V, Gate Source Voltage -8 to 8 V, Gate Source Threshold Voltage -1 to -0.3 V. Tags: Surface Mount. More details for SSM3J331R can be seen below.