The Extech PT300 is a Pressure Transducer for 300 PSI measurements with the SDL700 Pressure Meter/Datalogger and 407495 Heavy Duty Pressure Meter with Interchangeable Transducers. For air or non-corrosive/non-ionized gas. 6.4 mm (0.25 in) PS, 19 teeth per 2.5 cm/ 1 in with 1.2 m/ 3.9 ft cable.