The MJ4034 from MOSPEC SEMICONDUCTOR is a Bipolar Junction Transistor with Emitter Base Voltage 5 V, Emitter Cut off Current 5 mA, Collector Base Voltage 80 V, Collector Cut off Current 5 mA, Collector Emitter Voltage 80 V. Tags: Through Hole, NPN Transistor. More details for MJ4034 can be seen below.