Watts Aqualock 1/4" ODx1/2" MIP PEX Pipe Quick-Connect Adapter. This easy-to-install adapter features corrosion-resistant teeth that allow it to interconnect with multiple materials without special tools or tube inserts. Suitable for hot and cold water applications, it is made from durable polysulfone, a high-performance thermal plastic material. Designed for quick and easy connections to copper, PEX, CPVC, and polybutylene pipes, this adapter meets all National Plumbing Codes.