The SDL200 is a 4-channel datalogging thermometer that supports 6 thermocouple types (J, K, E, T, R, S) and 2 RTD (Pt100Ω) probes. It can display [T1, T2, T3, T4] or differential [T1-T2] readings and provides zero adjustment function for making relative measurements. It can store 99 readings manually and 20M readings via 2G SD card and record readings with real date and time stamp. The user can program the sampling rate from 1 to 3600 seconds. It also has min/max and data hold functions, auto power off and disable function, built-in PC interface. It comes with 6 AA batteries, four general purpose K type bead wire temperature probes, SD card and hard carrying case.