Autonomous small data logger with internal air pressure sensor system (barometer). The measuring principle is based on the measurement of the absolute pressure and the counter calculation of the measured air pressure in the data logger. Highlights: Baro in the data logger, 1 or 2-inch housing, plug-in pressure and temperature sensor, 433 MHz radio interface, memory for 250,000 series of measurements, batteries (lithium) can be changed by yourself, up to 10 years, optional connection options for meters and temperature measuring chains