GHP Self Inflating Camping/Hiking/Picnic Mattress Sleeping Pad w Pillow Rolls up with a carrying bag for easy transport and storage Material: Waterproof 190T polyester. Can be joined together to make a double-sized mattress if you purchase another one in our store. Self-inflating for convenient in use.Waterproof mattress which protects you from damp grass, sand, and bleachers. Perfect for hiking, climbing, camping, hunting,backpacking , trekking, traveling and vacation.