The SFT6039S.3 from Solid State Devices is a Bipolar Junction Transistor with Emitter Base Voltage 5 V, Base Emitter Saturation Voltage 2.2 to 4 V, Emitter Cut off Current 2 mA, Collector Base Voltage 80 V, Collector Cut off Current 0.5 mA. Tags: Surface Mount, NPN Transistor. More details for SFT6039S.3 can be seen below.