Polyester. .[Washable and Reusable Pee Pad] The pet pee pad has been tested repeatedly, and our pet pee pad can withstand 300+ machine wash and dry cycles. Just throw the pad into the washing machine, tumble dry on low temperature, and it will absorb just as well as the first time. Compared with other disposable pee pads, it reduces a lot of waste. Do not use bleach or softener. .[Fast Absorption and Leak-proof Puppy Pee Pad] The washable dog pee pad adopts 4 layers of thickened fast absorption and leak-proof materials, which can effectively prevent urine from flowing out and dry faster. Super absorbent polyester cotton can quickly absorb urine and odor. The waterproof TPU film of our puppy pee pad can effectively prevent urine from leaking onto the floor, no water leakage, no odor, keep your puppy in a dry and comfortable environment, while protecting the floor clean. .[Soft Surface and Non-slip Bottom] Soft and comfortable polyester knitted surface, no pilling, easy to clean. There is a lot of non-slip silicone on the bottom of the waterproof puppy pad, this design can maximize the life of the dog pad on hardwood floors or carpets. The durable double stitched edges of the dog pads extend the life of the pee pads. [2-Pack & Multiple Sizes] The 2-Pack Pet Dog Reusable Pee Pads come in 4 sizes, suitable for small, medium and large dogs. 24"x18", 24"x36", 36"x31", 36"x41", 36"x48". The size is the finished product measurement, there is a slight error, if you are not sure if the size is right for your dog, please choose the larger size. The 2-Pack is designed for easy replacement of pee pads, which can be used alternately after washing and drying. [Multi-Purpose] 2-Pack Reusable Potty Pads Pet Training Pads. Great for training dogs to potty, training puppies, dog potty pads, cage and fence pads, birthing pads, protecting furniture from pet hair and dirt, putting under food bowls, and perfect for senior dogs or incontinent pets. Can be easily folded and travel with your puppy!