The Fluke 1620A DewK continuously monitors temperature and relative humidity in laboratories, production areas and storage rooms. It accepts two interchangeable sensors, each measuring both parameters; the base package includes one sensor. The S version uses a standard-accuracy sensor and the H version a high-accuracy sensor. Calibrated temperature and humidity ranges are stated separately for each version. The instrument stores up to 400,000 time-stamped readings and provides alarms plus Ethernet/RS-232 connectivity. LogWare III and wireless RF communication are optional; 1621A-S/H Value Kits add a spare sensor and a LogWare III license. A 9 V backup battery maintains measurements during a mains interruption.