The compact Kalte-Set-Plus contains twice the high-pressure meter testo 549 i, the thermo-hygrometer Testo 605 i and the pliers thermometer testo 115 i for the measurement of pressure, temperature and humidity (air). In combination with a smartphone or tablet, the set is ideal for service and troubleshooting for air-conditioning and refrigeration systems, as well as for their installation. testo 549 i and testo 115 i can be quickly and easily directly at the pressure connection or the temperature measuring point. When working on far apart measuring points facilitate the application considerably - thanks to wireless connection to the smartphone or tablet.The measured values of both devices are supplied via Bluetooth ® to the Testo Smart probes app on your device and can be sent here comfortably and flexibly. The app also enables the automatic calculation of evaporative and liquefaction temperatures as well as heating/cooling performance. All measurement data are either as a diagram or i