Model G57C202A features a Kalrez diaphragm. This pump is part of the G57 air driven pump series by Flojet 

Ideal for applications, including chemical feed/transfer and dispensing, herbicide and water transfer, solvent applications, parts washers, ink transfer, and car wash systems, the G57 Series pumps are engineered for ultimate performance and reliability.

The G57 Series air operated diaphragm pump combines innovative features and relentless testing to offer a pump that has a long, trouble-free service life. The uniquely designed shuttle valve and check valves, together with high-performance capabilities, have created the ultimate in compact air operated diaphragm pump technology.

The G57 Series can supply up to 5 GPM (18.9 LPM). The high air inlet pressure capability makes it the ultimate pump that delivers fluid at the needed flow and pressure and is engineered to operate quietly with installed exhaust muffler.