Dow Filmtec XLE-2540 Extra Low Energy Commercial RO Membrane The Dow Filmtec TW30-2540 is tape-wrapped, making it more economical for commercial systems with less than 3 elements per housing Dow Filmtec tape wrapped-elements are made from the same high quality materials as industrial membranes, but do not have a hard outer shell May be cleaned over a wide range of pH levels (pH 1-13) for maximum cleaning effectiveness Free Chlorine Tolerance: &lt;0.1 ppm