This part is a kind of semiconductor called NTE123.

Function of this product has Silicon NPN Transistor General Purpose Audio Amplifier / Switch.

Manufacturers : NTE

Image and pinout :

Some of the text within the PDF file :

NTE123 Silicon NPN Transistor General Purpose Audio Amplifier, Switch Absolute Maximum Ratings: Collector–Emitter Voltage, VCEO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40V Collector–Base Voltage, VCBO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75V Emitter–Base Voltage, VEBO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6V Continuous Collector Current, IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800mA Total Device Dissipation (TA = +25°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 [ ... ]

NTE123 PDF Datasheet Download