... in the water, prevents the bacterium and algae's pipe wall multiplies. two, defend against the nature to be better, ... pore, also will not increase the gas movement, can enhance oxygen use factor 1-3 times, and will save the electrical ... energy, the economical cost. Outer diameter :22mmInner: 14 mmthick wall: 4mmM: 475gramsPacking number: 200 metersRequirements pressure : 50 kpa Hot sell ...