The Si4459BDY from Vishay is a MOSFET with Continous Drain Current -27.8 A, Drain Source Resistance 4.1 to 8.2 milliohm, Drain Source Breakdown Voltage -30 V, Gate Source Voltage -20 to 16 V, Gate Source Threshold Voltage -1 to -2.2 V. Tags: Surface Mount. More details for Si4459BDY can be seen below.