Made of oxford fabric. The bottom of this blanket is waterproof and sand proof. It can be used as a beach blanket, camping blanket, RV blanket, baby play mat, emergency blanket or throw blanket. It is the perfect choice for park, beach, sporting events, soccer games, tailgates, concerts, camping, hiking. Its foldable design with the handy strap makes it easier to be folded and stored, easy to carry. In short, whether it’s going out to play or indoor rest, it’s a good choice.