SDMN6 - Dual Port Manometer with Pressure Switch TesterFieldpiece SDMN6 Dual Port Manometer with Pressure Switch Tester The Dual Port Manometer has the ranges to measure gas pressure and the resolution needed to measure static pressure. Ideal for HVACR field service technicians, the SDMN6 can determine if the gas pressure coming into the house or out of the regulator are correct. The SDMN6 measures gas pressure up to 60 water column (WC) with a resolution of 0. 1 WC. In addition, the unit measures both