Shanghai United Compressor Co., Ltd. ( United OSD) is one of the most famous professional screw air compressor manufacturer in China. All products of United OSD are fully in accordance with ISO 9001 international standard as well as conform to ISO 14001 environmental requirements. United OSD is the one in three of whole China who has been given the license to manufacturing compressors from 15kw to 450kw at 2007, and, at the same year, we are granted the honor of Shanghai Energy-saving Products.