FMMT491 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 60 V
• Collector-Base Voltage, max: 80 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 1 A
• Collector Dissipation: 0.5 W
• DC Current Gain (h_fe): 100 to 300
• Transition Frequency, min: 150 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: SOT-23

Here is an image showing the pin diagram of this transistor.The FMMT491 transistor is marked as "491".The complementary PNP transistor to the FMMT491 is the FMMT591.You can replace the FMMT491 with the FMMT491Q.