BRITUM GPRS & WIFI wireless temperature & humidity USB data logger/Recorder, OLED display, 4000 data records capacity, coming with External temperature sensor 10 authorized phone numbers, SMS alarm when temp or humi out of normal range, configurable alarm/recover SMS Realtime logging upload data, view data on APP, control relay on APP or by SMS Logger data on PC software, PC software export records, flexiable data logging interval ( 1 minute up to 24 hours), monitoring software supports multiple T20 Send value by schedule, query current value by SMS, 4000 temperature record-set (auto rollback) An internal temperature and humidity sensor + An external temperature probe