A full range of stainless steel single screw unit its firstly used in this type of compressor manufactured by Kaishan.The compressor features natural water lubrication,is free from costly frequent maintentenance of dry screws and enables geometric compression at constant temperature.These are Chinese first oil-free air compresssors that reach level one energy efficiency.Oil-free lubrication compressors from Ganey are China-manufacyured,meet international standards and provide you the best value.