responsible, energy-saving, quiet and clean vacuum supply exalted efficiency by reduction of the water consumption and the ope 1, the system is proved to be capable of generating enough suction after strict testing; 2, the tubing and connecting are tightly sealed `and simple in structure which make it easy to install and uninstall. 3, fully automatic control is realized. the product can start, control and turn off the drainage of the sullage automatically; 4, the product simultaneously collects and disposes the sullage and drains out for environment-friendly pupose; 5, the product is designed to turn off postponedly after the usage to suck out oral secretion, blood, tooth debris and amalgam, etc. 6, the product is small size, light weight, silent and easy to install