The ApolloPEX 3/4 in. Brass PEX Barb Coupling is simple to install. ApolloPEX barb fittings are a key component of the most economical potable water piping systems. Also capable of integration into hydronic heating systems, ApolloPEX couplings can be secured into place using copper crimps, stainless steel pinch clamps or stainless steel crimp sleeves (all sold separately). The ApolloPEX 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.