The FRÍO Duo Pen Wallet is the most simple and convenient medication cooling system for travel. FRÍO cooling wallets offer Insulin Dependent Diabetes mellitus (IDD) sufferers the ultimate stylish accessory for the safe & convenient storage or transport of insulin. Frio Wallets are designed to keep Insulin and other medications constantly cool and safe at temperatures of up to 38C for at least 45 hours with no refrigeration or ice needed. It's an effective yet low-cost solution to the problem of keeping Insulin and other medication at a safe temperature without the need for refrigeration. Tested by the British Medical Devices Evaluation Unit and recommended by hospitals and clinics throughout the UK. Essential for daily use when away from home for any length of time or for travellers and holidaymakers.