This product is not waterproof. It is used by everyone as a panty liner. We have an increasing number of repeat customers. Both sides are double gauze, with 100% cotton fabric in the middle, making it a three-layer construction. It can be washed and used repeatedly. It should fit comfortably in your underwear without any discomfort. We hope you enjoy it as a reversible product. Size: Length 17 cm, Width 7 cm