The CPVC-CTS union is made of CPVC and is ideally suited for hot and cold water pressure distribution systems in residential and commercial applications. The CPVC-CTS transition union is used for the repair of a line and features a female socket x copper silicon alloy female NPT threaded connection that allows for CPVC-CTS tube to be connected to copper piping. Chlorinated Polyvinyl Chloride (CPVC) has proven to be an excellent material for hot corrosive liquids, hot and cold water distribution, and similar applications above the temperature range of PVC.