1. self-cooling cool time 3-6 hours 2.patented heat absorbing material 3.wash easily, reusable 4. Enough ready stocks ... energy from outside, this way it is used to cool body, including human's and animals'. phase change ... initial temperature is set at 30C, so the cool mat can keep the temperature constant at 30C ... for about 3 hours when being in use, and keep cool effect for over 4 hours ...