The RDXL4SD is a portable thermometer & data logger with built-in analysis functions from Omega Engineering. It can accept up-to 4 thermocouples from types J, K, T, E, R and S or 2 Pt100 Ω 2-wire sensors. The data loggers have a back lit display, showing up to 4 Channels simultaneously and capable of sampling, processing and displaying measurements without being connected to a computer. They include a real-time SD memory card data logger (1 to 16 GB capacity) built-in clock and calendar and real time data recorder. Auto sampling time can be set from 1 to 3600 seconds and the user can also log data manually. These real-time data loggers save measured temperature data, along with the time information (year, month, date, minute, second) into the SD memory card. Data can be subsequently downloaded to Excel for analysis.