By keeping the outside of your ArctiCreeL soaked with water at all times while it is in use it will keep your fish in excellent 'just out of water' condition. The outside covering is made of flax (linen) which absorbs and holds a great deal of moisture. The evaporation which takes place on the outside surface of the ArctiCreeL greatly reduces the temperature within the creel, keeping the fish cool and solid at all times. The material in the outside covering is the same as that which is used in the Desert Water Bags and the cooling process through evaporation which has long been appreciated in a water bag is the same.