Pine Brook, N.J.-based John Guest USA’s Single Check Valves are now available in 1/4” O.D. size as well as its existing 3/8” O.D. size. They provide protection against fluid backflow and can be used with most types of fluids. Designed with Super Speedfit® technology, the check valves feature the same simplicity as the company’s fittings for providing a fast and secure way of connecting plastic or soft metal tubing without the use of tools. The valves afford the most reliable and cost effective solution to tubing connections.