what is thermal phone case

what is thermal phone case,prevent OVERHEATING in The Sun, Prevent Lower Temperatures to Extend Battery Life.

Thermal Case,helps prevent the temperature of the mobile phone from becoming too low,but it has no heating function, so as to extend the battery life. It is suitable for the mobile phone to be in a low temperature environment for a long time. It is made of heat preservation materials and materials that can prevent thermal radiation in accordance with the technical principles.