The testo 552 is a digital vacuum measuring instrument for the evacuation of refrigeration systems and heat pumps. It measures even the smallest absolute pressures and provides highly precise information on the status of the dehumidification of a system. The testo 552 is the only digital vacuum measuring instrument whose absolute pressure sensor, in contrast to other sensor technologies, no longer needs to be serviced, and still provides highly accurate measurement results. Thanks to the battery life of up to 2400 hours with two conventional AA batteries, you can use the testo 552 in continuous operation for 100 days without changing the battery. Its robust construction makes it suitable for daily use, and protects from dirt and water.