TUSY leak-proof cooler backpack are made of double-sided waterproof material and and resistant to punctures, and abrasions. It would be durable and strong enough after being filled with fruit & drinks. It is ideal companion gear for lunches, beach picnics, park, tail-gating, hiking, camping or backyard use. The inner material of the soft cooler is high density foam and the surface is waterproof material & airtight zipper which can ensure the cool air stays in cooler. More than 48 hours extra long cooling insulation time under the ice cube capacity in the insulation bag is 50% or more , will keep the food fresh and drinks cool.