Slide fittings, also known as PEX expansion fittings, create a secure, full-flow connection that is considered one of the most reliable methods for joining PEX-A tubing. The system works by using an expansion tool to temporarily stretch the PEX pipe and a PEX sleeve (or ring) together. The fitting, which has a larger inner diameter than other types, is then inserted into the expanded pipe. As the PEX memory contracts back to its original size, it creates immense radial pressure on the fitting, forming an exceptionally strong, permanent, and leak-proof seal. This method avoids obstructing the pipe's pathway, ensuring maximum water flow and pressure with minimal turbulence.