The MMBT4401 from Diotec Semiconductor is a Bipolar Junction Transistor with Emitter Base Voltage 6 V, Base Emitter Saturation Voltage 0.75 to 1.2 V, Emitter Cut off Current 100 nA, Collector Base Voltage 60 V, Collector Cut off Current 100 nA. Tags: Surface Mount, NPN Transistor. More details for MMBT4401 can be seen below.