The STD16N50M2 from STMicroelectronics is a MOSFET with Continous Drain Current 13 A, Drain Source Resistance 240 to 280 Milliohm, Drain Source Breakdown Voltage 500 V, Gate Source Voltage - 25 to 25 V, Gate Source Threshold Voltage 2 to 4 V. Tags: Surface Mount. More details for STD16N50M2 can be seen below.