To ensure a waterproof seal, be sure to roll the top a minimum of 3-4 times, and securely close the buckle. These Dry Bags bodies are made of awesome-premium material, aesthetic and comfortable, but heavy duty and durable tough, stay soft and flexible even in the coldest weather. You can treat them as waterproof school bag, waterproof backpack, waterproof gear bag, waterproof dry bag, waterproof outdoor bag, scuba dive bag,waterproof beach bag, kayak bag, camping bag, underwater bag, waterproof pouch, waterproof travel backpack, marine dry bag, boating bag , sailing bag, canoeing bag, dry storage bag, compression dry bag, fisherman bag, hunting bag, hiking bag, adventure waterproof backpack,wet dry bag, ect. They have a funny name called "tagalong", as they can tag along with you wherever you like, traveling, swimming, diving, surfing, rafting, outdoor walking, camping, water sports, kayaking, boating, white water Rafting, dive gear, island hopping, skiing, snowboarding, whatever. They will keep your personal stuff clean, safe and dry. If you need ,they can float in a lake, river, or ocean.