Dwyer 2203 Magnehelic® Differential Pressure Gauge is a reliable and accurate device for measuring differential pressure in air and non-combustible gases. With an IP67 enclosure rating and a die cast aluminum housing, it can withstand harsh environments. It features a 4" diameter dial face and includes standard accessories for easy installation. The gauge has an accuracy of ±2% throughout the range at 70°F and a pressure limit of -20 in Hg to 15 psig.