Copper Press x PEX Crimp style adapters are used to transition from a copper pipe to PEX pipe using press and crimp methods. Press side is the same style as most press fittings on the market, including brands such as Viega, Apollo, Nibco and others. PEX side is crimp style and is compatible with PEX crimp or cinch/clamp methods and all types of PEX pipe (A, B, C).