The BC817-25W from Diotec Semiconductor is a Bipolar Junction Transistor with Emitter Base Voltage 5 V, Emitter Cut off Current 100 nA, Collector Cut off Current 100 nA, Collector Emitter Voltage 45 V, Continuous Collector Current 500 mA. Tags: Surface Mount, NPN Transistor. More details for BC817-25W can be seen below.