significant function, small voice, stable speed, and continuously adjustable speed. In a wide range of speeds of the liquid solution for precise and stable stirring, especially suitable for stirring large volume of samples; with mechanical timing; with another control box, can be far away from the table operation. It is indispensable essential equipment for laboratory stirring of various liquid phase chemical reactions. The instrument is widely used in colleges and universities, environmental protection, health and epidemic prevention, medical treatment, metallurgy, chemical industry, food, and other laboratories.