CollecTex is the combination of 2 superior technologies in 1 sponge. A patented 3-dimensional foam structure that quickly traps larger dirt particles. A 50% more absorbent foam that absorbs even the finest dirt particles. Flexible sponge wrings out easily and resists mold and mildew. Built in scrub strip for getting out tough scuff marks or ground in dirt and grout lines. Fits 8.5" roller mops including O-Cedar , Roll-O-Matic , and Vileda .