The STL33N60DM6 from STMicroelectronics is a MOSFET with Continous Drain Current 21 A, Drain Source Resistance 125 to 140 Milliohm, Drain Source Breakdown Voltage 600 V, Gate Source Voltage - 25 to 25 V, Gate Source Threshold Voltage 3.25 to 4.75 V. Tags: Surface Mount. More details for STL33N60DM6 can be seen below.