The MMBT4403 is an NPN SOT-23 RoHS compliant transistor manufactured by SLKORMICRO. This type of transistor is commonly used in low-power and low-noise circuits, such as amplifiers, switches, level shifters, and motor control circuits. It has a maximum collector current of 350mA, a maximum collector-emitter voltage of 40V, and a maximum power dissipation of 500mW. It is designed for high accuracy and high frequency performance, and its low gate current leakage makes it ideal for low-power applications. It also has an excellent frequency response and can be used in different configurations.