The STD4N62K3 from STMicroelectronics is a MOSFET with Continous Drain Current 3.8 A, Drain Source Resistance 1700 to 200 Milliohm, Drain Source Breakdown Voltage 620 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 3 to 4.5 V. Tags: Surface Mount. More details for STD4N62K3 can be seen below.