Dwyer 4000-40MM Capsuhelic® Differential Pressure Gauge is a reliable and accurate instrument suitable for measuring differential pressures in a range of applications. It features a temperature range of 20 to 200°F and an accuracy of ±3% of FS at 70°F. The gauge is housed in a die-cast aluminum enclosure with optional forged brass housing available. It can be used with air, gases, oil-based liquids, and water-based liquids. The gauge has a 4" diameter dial face and comes with necessary accessories for easy installation.