Premium split nylon/polyester blend microfiber provides optimal damp mopping performance. Dense 3 - 5 micrometer quality fiber removes more dust, dirt and microbes than conventional cleaning products. Advanced hook-and-loop backing...holds-up under harsh laundering conditions and attaches pads more securely. Durable pad construction...third party tested tough...withstands more than 300 launderings. Double finished edges retain mop shape with use over time. Patent Pending Zig-Zag design packs 17% more split microfiber into each mop. Durable mop construction - third party tested tough. Withstands more than 500 launderings, 200 with bleach. Proven to clean floors 45% better than string mops, 25% better than conventional microfiber