Analog Manometer Pressure Range -8 to 8 in wc For Tubing Diameter 0.187 in Maximum Operating Pressure 100 psi Maximum Pressure 8 in wc Minimum Pressure -8 in wc Scale Units in wc Series 1223 Manometer Type Flexible U-Tube Housing Material Plastic Includes Gas Pressure Kit No Fluid Color Red Includes 1 oz Red Gage Fluid Magnetic Mounting Clips Plastic Tubing Tube Adapters Tube Clamp and Nylon Tubing Connections Lens Material Butyrate Minor Graduations 0.1 in wc