The Silica Gel Car Moisture Absorber ingredient is a blue silica gel, it's a patented color changing humidity indicator changes the dehumidifiers color from blue to pink when it is time to evaporate the moisture it has collected. This is easily done by placing the dehumidifier into a microwave for 4 minutes at 600W. The dehumidifier can prevent long-term moisture damage to sensitive valuables, a good accessory for any small closed place. A patented color changing humidity indicator changes its color from blue to pink when it reaches its absorption capacity. Place it into a microwave for up to 4 minutes at 600W to evaporate the moisture.