Testo 510 - Differential Pressure Meter, protection cap, belt holder, 2 x connection hoses, wrist strap, calibration protocol. Differential pressure measurement on gas hot water heaters or on filters of air conditioning systems, and also flow measurements in ventilation ducts using a Pitot tube: the compact testo 510 differential pressure measuring instrument, which comes with a silicone connection hose and other useful accessories, can help you maintain and install systems in the sanitary and HVAC sector. • Illuminated display • Magnets on the rear allow hands-free work • 50 hours of battery life • 10 selectable units • Flow measurement possible with a Pitot tube (available as an option)