The STB20NM60 from STMicroelectronics is a MOSFET with Continous Drain Current 20 A, Drain Source Resistance 250 to 290 Milliohm, Drain Source Breakdown Voltage 600 V, Gate Source Voltage -30 to 30 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Surface Mount. More details for STB20NM60 can be seen below.