Southern Cogen Systems Pvt. Ltd. Supplies Wide Band Non Membrane Type Coarse Bubble. Southern Cogen Systems Pvt. Ltd. Is the Manufacturer of gas burners, duo block gas burners and oil gas burners used in industrial furnaces and boilers. Wide Band Non Membrane Type Coarse Bubble is available in PVC plastic. Wide Band Non Membrane Type Coarse Bubble has the feature of a clog- free design, oxygen transfer rates of 0.5 to 0.8% per foot of submergence. They have a reliable alpha value and are designed to economically cover the tank floor. The design of the air flex band is longer that the typical stainless wide band on the market, for good reason. It offers better floor coverage at a more economical price.