... for a variety of long axis of liquid pumps, submersible pumps, submersible sewage pumps and other equipment for the best. 2, ... in more than 10 times. 3, transplant vacuum principle, self-priming performance, stable and reliable, in particular, used the term ... electric air control valve", truly a "one-draining, life-long self-priming." 4, little vibration, low noise, mobile and flexible, demolition ...