Different PEX types

There are three different types of PEX, PEX-a, PEX-b, and PEX-c, based on their manufacturing methods. The different methods create pipe that is cross-linked to different degrees and uniformity. Rule of thumb: The higher the degree and uniformity of cross-linking, the more durable and flexible the pipe. PEX-a offers the highest degree of cross-linking at around 85%; PEX-b, 65 to 70%; and PEX-c, 70 to 75%.