How fast does Ereada® heating mat get to the highest temperature level?

If the amethyst or gemstone mat is covered with Ereada® 3-D Protector or a thick blanket or if a person lays on the heating mat, it starts to heat immediately and gets to the highest temperature in about 30-45 minutes.

If the mat is uncovered and the ambient temperature is low, and the airflow is high, it may take the mat 1-2 hours to reach the maximum possible level, but it may never heat up to the same level was covered.