A highly integrated Multifunction Temperature Calibrator featuring several patented technologies, the ADT221A is an ultra-compact, rugged, and easy to use hand-held device for sourcing, simulating and measuring temperature, and electrical signals. Its smartphone-like menu and interface make the operation simpler and easier. The ADT221A is ideal for calibrating, maintaining, and troubleshooting process instrumentations. Automation and documentation capabilities make the ADT 221A a turnkey solution.