The QEC_GX is used with Zurn® Non-Barrier PEX® tubing in potable water applications. Not for use in reverse osmosis systems or in areas with known localized aggressive water chemistries. Manufactured from EcoBrass®,C69300. These fittings, as a system with Zurn® PEX® tube and Zurn® PEX® reinforcing rings are pressure rated at 160 psi at 73 deg F, 100 psi at 180 deg F and 80 psi at 200 deg F. These fittings are 3rd Party certified as complying with the following standards: NSF/ANSI Standard 61, NSF/ANSI Standard 372 (Low Lead), ASTM F1960, CSA B137.5.