蓝色是硅胶

blue silica gel mainly used for absorbing moisture, anti-rusting of instruments, gauges and equipment in the enclosed conditions. After absorbing moistures, it turns from blue to red, visually indicating the relative humidity of the given environments. when being used with prdinary silica gel or drier. it indicates to which extent the drier absorbs the moisture and judges the relative humidity of a given environment. it is widely used as silica gel drier for the packing of percision instruments, leathers, shoes, clothes, foodstuffs, medicines and household electric appliances, etc.