Ideal for dry control of desiccator cabinets. Moisture is absorbed through the perforations in the aluminum case, which contains silica gel. This 2x4" canister maintains a safe level of humidity in 3 cu. ft (0.8 cu. meter) area. When the monitor window turns green, the silica gel is saturated. It can be regenerated in a 300°F (150°C) oven in about 3 hours. The monitor window will be pink in color when recharged.