2SD731 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 120 V
• Collector-Base Voltage, max: 170 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 7 A
• Collector Dissipation: 80 W
• DC Current Gain (h_fe): 40 to 200
• Transition Frequency, min: 7 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-3P

Here is an image showing the pin diagram of this transistor.Sometimes the "2S" prefix is not marked on the package - the 2SD731 might only be marked "D731".The complementary PNP transistor to the 2SD731 is the 2SB695.