The STB41N40DM6AG from STMicroelectronics is a MOSFET with Continous Drain Current 41 A, Drain Source Resistance 50 to 65 Milliohm, Drain Source Breakdown Voltage 400 V, Gate Source Voltage - 25 to 25 V, Gate Source Threshold Voltage 3 to 5 V. Tags: Surface Mount. More details for STB41N40DM6AG can be seen below.