The MJD340 NPN transistor is a 500mA, 300V, surface mount device that is manufactured by Blue Rocket. It is RoHS compliant, meaning it has lead-free soldering points. It comes in a TO-252 package, which is a hermetically sealed, surface-mountable plastic package with two leads. It is ideal for signal switching and general purpose amplifier applications. The MJD340 NPN transistor can be used in various electronic circuits, such as power supplies, communication systems, and motor drives. It is suitable for use in low-noise and low-power applications.