Prowin Tools Company's air-powered double-diaphragm pumps are highly praised for cost effective in a wide range of special applications. They can delivery sludges and slurries with grit, high viscous liquids, chemicals, cement, etc. The products will not be damaged while idling for a long period of time. They can be safely used in hazardous environments, need no control equipment and cause no electrical danger. The pressure of the outlet of the pumps could be regulated when the machine is running, and there is no need to install any high-cost speed-changeable motor or drive device.