DSPPA is a professional public address system manufacturer, with over 10 years of experience in this line. In order to produce high quality outdoor public address systems, portable public address systems, amplifiers, public address speakers, digital conference systems and more products, we have imported or built up a series of inspection equipment. They include ROHS testers, constant temperature and humidity chamber, salt spray tester, etc. These pieces of inspection equipment ensure the quality of our products. As a result, we are the public address system supplier of 2008 Beijing Olympics and the supplier of Expo 2010 Shanghai China. Please feel free to contact us for your public address system needs! Thank you!