NB-45-5-B is a type of semiconductor manufactured by Newbrand. It is an NPN transistor, meaning it is a three-terminal, active-lown, amplifying device. This type of semiconductor can be used for a variety of amplifying, switching and other applications including audio, radio and voltage regulators. This transistor has a Collector-Emitter Voltage of 45 volts, a Collector-Base Voltage of 100 volts, and an emitter-base voltage of 5 volts. It also has a Collector current of 500 mA, and an emitter current of 5 mA. This transistor is widely used in a variety of circuits.