The John Guest union connector makes connecting OD tubing sizes quick and easy. Manufactured in gray acetal with food grade nitrile O-ring, these fittings are suitable for foodstuff and potable liquids. They are also suitable for air and inert gases therefore can be used for CO2 and nitrogen beverage gas lines, pneumatics, vacuum as well as other applications. Features: Push-fit Technology creates reliable, leak-free connections Used to connect OD tubing sizes Compatible with plastic or copper OD sized tubing Connect, disconnect, and reconnect in seconds without tools Food Quality and suitable for potable liquids and pure water applications Can be used for air/pneumatic & vacuum applications Acetal body with Nitrile O-Ring Made with lead free materials Working pressure and temperature:  Max. 150 psi at 68° F Max. 100 psi at 150° F JG gray acetal is suitable for both compressed air and water (buna-n seal).