The STB30N65M5 from STMicroelectronics is a MOSFET with Continous Drain Current 22 A, Drain Source Resistance 125 to 139 Milliohm, Drain Source Breakdown Voltage 650 V, Gate Source Voltage - 25 to 25 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Surface Mount. More details for STB30N65M5 can be seen below.