The cloths contain preservative silver chloride to prevent growth of bacteria in the cloth. It's made of 50% viscose and 50% polyester. The Vileda Washing Cloths are a pack of 25 multifunctional cloths designed for kitchen and household use. Made in Germany, these blue cloths are perfect for various cleaning tasks, making them a convenient and practical addition to any household. With the trusted Vileda brand, you can be sure of their quality and effectiveness in keeping your kitchen clean and hygienic.