For mixing purposes, a Black Coarse Bubble Diffuser can be used in a wastewater treatment plan's equalization tank. It is used in air stripping, small or package plant systems, auto-thermophilic aerobic digestion, mechanically thickened sludge applications and aerobic digestion applications. This is very effective and safe to use. Black Coarse Bubble Diffuser is simple to set up and use, needs little maintenance, and provides application versatility and mechanical reliability. EPDM is the material used in the membrane.