RLS Press Fittings were specifically designed and engineered to join copper tube in high-pressure HVAC and refrigeration systems. Our patented RLS Press Fittings are fully registered and listed to UL207 for pressures up to 700 PSI. These first-of-their-kind fittings connect quickly and easily using an RLS-approved press tool and jaws, replacing the time-consuming practice of manually brazing joints. The pressing procedure is similar to the one used with water press fittings. RLS Press Fittings, however, were developed to withstand the high pressures found in HVAC/R systems.