The CMPT491ETR from Central Semiconductor is a Bipolar Junction Transistor with Emitter Base Voltage 5 V, Base Emitter Saturation Voltage 1.1 V, Emitter Cut off Current 100 nA, Collector Base Voltage 80 V, Collector Cut off Current 100 nA. Tags: Surface Mount, NPN Transistor. More details for CMPT491ETR can be seen below.