Why does the backing of the bathroom rugs turn yellow in some places? The backing of the bathroom mat is made of PVC material. When PVC comes into contact with the air, it will oxidize and turn yellow, which is a normal phenomenon and will not affect the function of the product. M achine washing or only hand washing? Machine washing or hand washing is ok. We recommend two or more for easy washing. Wash the bath mat every two weeks to keep it hygienic . It's probably best to tumble dry on low or hang dry it to avoid any shrinking. W hat makes our product unique? Using Nature's wisdom as our source of inspiration, Nulubuu continuously created innovative household products with passion. Utilizing advanced soft materials, experienced workmen, we offer chic and comfy items of high quality to decorate your home. The Nulubuu Bath Rug have so many benefits, it's a great choice to any bathroom! Super absorbent and quick-drying ability Extremely soft – Each microfiber pile is about 1'' long Non slip PVC Backing Pet friendly Read more The Bath Mats provides a luxurious, soft pile made of 100% chenille that soothenes tired feet and shields toes from the cold floor. Its special microfiber construction offers you extra softness, 1" long microfiber shag, makes your feet surrounded by thousands of individual microfiber shags. Read more Soft microfibers with 6mm sponge inside, they are soft and odorless; Non-slip backing is made of high quality PVC material. This anti-skid backing has practically slip resistance on the floor surface. You can feel secure having our product in your home. Read more The ultra-absorbent bath rugs microfiber surface quickly soaks up an impressive amount of water and keeps it contained. Even more, the bathroom mats dries quickly for a supreme comfort from one use to the next. Read more