The CZT31C from Galaxy Century Microelectronics is a Bipolar Junction Transistor with Emitter Base Voltage 5 V, Emitter Cut off Current 1 mA, Collector Base Voltage 100 V, Collector Cut off Current 20 µA, Collector Emitter Breakdown Voltage 100 V. Tags: Surface Mount, NPN Transistor. More details for CZT31C can be seen below.