The MMBT3904TB_R1_00001 from PANJIT Semiconductor is a Bipolar Junction Transistor with Emitter Base Voltage 6 V, Base Emitter Saturation Voltage 650 to 950 mV, Collector Base Voltage 60 V, Collector Cut off Current 50 nA, Collector Emitter Breakdown Voltage 40 V. Tags: Surface Mount, NPN Transistor. More details for MMBT3904TB_R1_00001 can be seen below.