... box for cooling insulin in hot weather B:Power supply AC110-240V , DC12V ,battery C:Digital temp display ... , outdoor activities, or bussiness trip, or don't want to store insulin in a shared fridge in school, work ... power or household power.3. Many ways for power supply: 12V DC vehicle, 110V-240V AC, 7.4V ... heating while air temperature below 0 Celsius, heating up to 12 Celsius at -10 Celsius.6. 2-8 ...