Arctic Hayes Digital Differential Pressure Meter Kit The Arctic Hayes Digital Differential Pressure Meter Kit is a professional tool for domestic tightness testing and other pressure measurement applications. With a clear digital display and 11 pressure units, this compact kit gives you accurate and versatile pressure readings for installers, engineers and technicians. Has max/min pressure functions, data hold and record mode and backlit screen, it’s perfect for precise and fast diagnostics. The kit comes with hoses, battery, carry case and instructions – so it’s a complete ready to go solution. Features Multi-Unit Measurement – Measures in 11 units: mbar, psi, inches