Composed of strong and sturdy lead free DZR brass, these brass crimp couplers are ideal for connecting 2 same-sized PEX pipe together with crimp or clamp rings, and do not require any glue, soldering, or additional tools. Compatible with PEX and PE-RT pipe, these fittings feature a minimum working temperature of 33 degrees F at 160 PSI, and a maximum working temperature of 200 degrees F at 80 PSI.