:The B553-2 is a 25A, 280VAC ISO-QC Mod Diode SCR module, manufactured by Sensata. It is a discrete semiconductor module that is designed to be used in power switching applications. The module can handle up to 25A of current and operates at a voltage up to 280VAC. It is equipped with a reverse current block (RCB), which prevents a negative voltage when an output is shorted, and is designed to reduce current spikes and protect against AC line noise. The B553-2 also features diagnostic LED indicators to easily monitor the power condition. The module has a quick connect (QC) terminal design, which allows for fast and easy connection to the system wiring.