This part is a kind of semiconductor called MRF454.

Function of this product has RF POWER TRANSISTOR NPN SILICON.

Manufacturers : Tyco Electronics

Image and pinout :

Some of the text within the PDF file :

SEMICONDUCTOR TECHNICAL DATA Order this document by MRF454/D The RF Line NPN Silicon RF Power Transistor Designed for power amplifier applications in industrial, commercial and amateur radio equipment to 30 MHz. • Specified 12.5 Volt, 30 MHz Characteristics Output Power = 80 Watts Minimum Gain = 12 dB Efficiency = 50% MAXIMUM RATINGS Rating Collector–Emitter Voltage Collector–Base Voltage Emitter–Base Voltage Collector Current Continuous Total Device Dissipation @ TC = 25°C Derate above 25°C Storage Temperature Range Symbol VCEO VCBO VEBO IC PD Tstg Value 25 45 4.0 20 250 1.43 –65 to +150 Unit Vdc Vdc Vdc Adc Watts W/°C °C MRF454 80 W, 30 MHz RF POWER TRANSISTOR NPN SILICON THERMAL CHARACTERISTICS Characteristic Thermal Resistance, Junction to Case Symbol RθJC [ ... ]

MRF454 PDF Datasheet Download