This 1/4" dual check valve backflow preventer for carbonated beverage machines prevents the reverse flow of contaminated water, such as carbon dioxide gas and carbonated water, from entering into the potable water supply due to backpressure backflow. It consists of a stainless steel body construction with internal rubber components and is designed for continuous or intermittent pressure applications. It has female NPT end connections. It is ideal for use on post-mix carbonated beverage equipment and dispensing equipment for tea and coffee. Maximum working pressure is 200 psi (13.8 bar).