2N3500 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 150 V
• Collector-Base Voltage, max: 150 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 0.3 A
• Collector Dissipation: 1 W
• DC Current Gain (h_fe): 40 to 120
• Operating and Storage Junction Temperature Range: -65 to +200 °C
• Package: TO-39

Here is an image showing the pin diagram of this transistor.You can replace the 2N3500 with the 2N3440.