ESD/anti-static desiccant and humidity indicator cards are designed to manage or eliminate humidity from items during shipping and storage. Desiccants are tiny pieces of absorbent material such as clay, silica gel or carbon. They are usually placed in small pouches and put into storage or shipping containers. Humidity indicator cards are placed inside packages to monitor humidity levels. Humidity is indicated by blue crystals that dissolve at specified humidity levels, leaving a blue spot at the indicated level.