SZ series liquid ring vacuum pump and compressor are remodeled on the basis of the product produced by FSU imported in 60s or 70s. Since the product have lower efficiency and lower vacuum degree, this series have been faded gradually at present. Our company have years of professional production experience of liquid ring vacuum pumps, so we still retain the production scheme of this series. But now we only produce the pump for maintenance and change the old pump. We do not recommend this series as new items to introduce to users..