The TP120H058WS from Transphorm is a GaN Power Transistor with Gate Threshold Voltage 3.2 to 4.7 V, Drain Source Voltage 1200 V, Drain Source Resistance 58 to 119 milli-ohm, Continous Drain Current 28 A, Pulsed Drain Current 78 A. Tags: Through Hole. More details for TP120H058WS can be seen below.