The 2SC1061 is a NPN Power Transistor in To-220 package. It has a DC current gain from 35 to 320 and transition frequency of 5MHz. It is commonly used in high power amplifier application along with its complementary PNP part 2SA671.
The 2SC5200 is a high power NPN Transistor with a collector to emitter voltage of 230V and collector current of 30A. The transistor is available in TO-264 package and is commonly used Amplifier designs.
2N3055 is a general purpose NPN power transistor manufactured with the epitaxial base process, mounted in a hermetically sealed metal case. The device is designed for general purpose switching and amplifier applications.