The Si3421DV from Vishay is a MOSFET with Continous Drain Current 8 A, Drain Source Resistance 16 to 27 milliohm, Drain Source Breakdown Voltage -30 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage -1 to -3 V. Tags: Surface Mount. More details for Si3421DV can be seen below.