The STD5N95K3 from STMicroelectronics is a MOSFET with Continous Drain Current 4 A, Drain Source Resistance 3000 to 3500 Milliohm, Drain Source Breakdown Voltage 950 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Surface Mount. More details for STD5N95K3 can be seen below.