The 2N4857 from Microchip Technology is a RF Transistor with Supply Voltage 40 V, Voltage - Drain-Source (Vdss) 0.5 V, Voltage - Gate-Source (Vgs) -40 V(Gate-Source Breakdown Voltage), Drain Current 20 to 100 mA, Collector Current (Ic) 0.1 A. Tags: Through Hole. More details for 2N4857 can be seen below.