This Copper - Aluminum Radiator has 6 advantages: 1. High radiation efficiency. 2. We have certificate from nation appointed inspection department. Relying on strict quality management and considerate service, factory has passed ISO9001 international quality system certificate, measure system certificate and product quality certificate. We also have 3A certificate for our product. 3. Pressure resistance 1.2Mpa, fit for high building (50), 100% argon-arc welding, better than capillary brazing. 4. Double ingredient inside anticorrosive, safe to be used under the water condition of 3