The EPC2057 from Efficient Power Conversion is a GaN Power Transistor with Gate Threshold Voltage 0.7 to 2.5 V, Drain Source Voltage 50 V, Drain Source Resistance 6 to 8.5 milli-ohm, Continous Drain Current 9.6 A, Pulsed Drain Current 66 A. Tags: Die. More details for EPC2057 can be seen below.