The cooling bag keeps insulin cool. It consists of a cooling case and protecting case. Soak the cooling bag in cold water for 45-60 minutes. The special gel is evenly distributed and absorbs the water. Wring out excess water. Place the insulin pens in the poly bag supplied and then the cooling bag. The bag can then be placed in the corresponding protection case. It will remain at room temperature for four days and can be reused multiple times.