The MJD3055T4 from STMicroelectronics is a Bipolar Junction Transistor with Emitter Base Voltage 5 V, Emitter Cut off Current 0.5 mA, Collector Base Voltage 70 V, Collector Cut off Current 50 µA, Collector Emitter Voltage 60 V. Tags: Surface Mount, NPN Transistor. More details for MJD3055T4 can be seen below.