The Apollo PEX 1/2 in. Brass PEX Barb x 1/2 in. Female Pipe Thread Adapter Jar (25-Pack) is simple to install. Apollo PEX barb fittings are a key component of the most economical potable water piping systems. Also capable of integration into hydronic heating systems, Apollo PEX adapters can be secured into place using copper crimps, stainless steel pin. clamps or stainless steel crimp sleeves (all sold separately). The Apollo PEX system is a comprehensive piping system comprised of brass fittings, poly alloy fittings, manifolds, valves, fasteners, tools and tubing designed for implementation in water delivery systems, simple or complex.