Scrub roller mop refill has a microfiber wave sponge for better spill pick up and requires less water and cleaning detergents to clean effectively. Improved water absorption cleans large floor areas between wringing and eliminates friction between sponge and floor for smooth glide. Grabs more non-visible dirt and cuts through grease to clean more effectively. Refer to model No. 133940 (SKU 630888) Power Scrub roller mop.