2N4427 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 20 V
• Collector-Base Voltage, max: 40 V
• Emitter-Base Voltage, max: 2 V
• Collector Current − Continuous, max: 0.4 A
• Collector Dissipation: 3.5 W
• DC Current Gain (h_fe): 10 to 200
• Transition Frequency, min: 175 MHz
• 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 2N4427 with the 2N3866.