The MURS340T3G Diode Standard 400 V 3A Surface Mount SMC is an SMT (Surface Mount Technology) diode, manufactured by ON Semiconductor, that is used to protect against high-voltage transients. It features a reverse stand-off voltage of 400 V, a maximum forward voltage drop of 1 V, a peak pulse current of 3A, and an operating temperature range of -65°C to 175°C. This diode is designed for surface mounting on printed circuit boards, and is suited for general purpose rectification, freewheeling, and polarity protection applications.