SharkBite large diameter fittings are available in 1-1/4 in., 1-1/2 in. and 2 in. sizes. These fittings are compatible with copper, CPVC, PEX, PE-RT and HDPE pipe in any combination. Just insert the pipe and stainless-steel teeth bite down and grip tight, while a specially formulated O-ring compresses to create the perfect seal. Push-to-connect fittings are designed for potable water (including underground or behind the wall) and radiant heating applications with no access panels required. Always use PEX Stiffeners, (Sold Separately) when using PEX pipe with large diameter fittings.