The SFT4100M from Solid State Devices is a Bipolar Junction Transistor with Emitter Base Voltage 7 V, Base Emitter Saturation Voltage 1.12 to 2 V, Emitter Cut off Current 1000 µA, Collector Base Voltage 250 V, Collector Cut off Current 5000 µA. Tags: Through Hole, NPN Transistor. More details for SFT4100M can be seen below.