Working principle:There are two symmetrical working chambers in the pump, each fitted with a diaphragm, and the central connecting rod will be integrated into one. Compressed air enters the valve from the pump inlet, and is introduced into one of the chambers through the valve body to facilitate the movement of the pump. The diaphragm chamber, while the other chambers are exhausted. Once the end of the stroke is reached, the gas distribution mechanism automatically introduces compressed air into the other working chamber, pushing the diaphragms in opposite directions, causing both diaphragms to move back and forth in unison.feature:Brand new top qualityAir operated double diaphragm pumpWith 1" inlet and outlet1/2 inch air intake1/8" Maximum Diameter Suspended SolidsGreat for use with waterIdeal for use with low viscosity petroleum fluidssturdy constructionSpecification:Product: Diaphragm PumpType: Double DiaphragmOperation Type: PneumaticModel: Qby4-25lBody Material: AluminumInlet port: 1 in (25 mm)Outlet Port: 1" (25mm)Air Inlet Size: Npt 1/2" (12.7mm)Average Air Consumption: 38 CfmMaximum flow: 9 M3/H (35 Gpm)Suction: 0-5 M (0-16.4 Ft)Maximum suspended solids: 3 mm (1/8 inch)Max Head: 84 M (275.59 ft)Maximum Psi: 120 PsiMaximum temperature: 150°FSelf-priming dry: 3 M (10 Ft)Hygroscopic: 4.6 M (15 Ft)Manifold Connection: SingleValve Type: BallBall Material: AcetalCheck Seat Material: PolypropyleneDiaphragm Material: Nitrile RubberPackage Dimensions: 35 X 26 X 23 cm (13.78 X 10.24 X 9.06 inches)Gross Weight: 9.86 kg (21.74 lb)Package Contents:1 X Air operated double diaphragm pump1 X Product Brochure