The MPSA18 from Central Semiconductor is a Bipolar Junction Transistor with Emitter Base Voltage 6.5 V, Collector Base Voltage 45 V, Collector Cut off Current 50 nA, Collector Emitter Breakdown Voltage 45 V, Collector Emitter Voltage 45 V. Tags: Through Hole, NPN Transistor. More details for MPSA18 can be seen below.