2N6558 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 300 V
• Collector-Base Voltage, max: 300 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 0.5 A
• Collector Dissipation: 10 W
• DC Current Gain (h_fe): 40 to 180
• Transition Frequency, min: 200 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-202

Here is an image showing the pin diagram of this transistor.The KST42 (SOT-23), MMBTA42 (SOT-23) and PZTA42 (SOT-223) is the SMD version of the 2N6558 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2N6558 with the 2N6559.