Desiccators are sealable containers with desiccants used for protecting moisture-sensitive items such as cobalt chloride paper. A common use of desiccators is to preserve chemicals which are hygroscopic in nature. However, it is not very effective for preserving some other highly moisture-sensitive substances like the alkali metals, which reacts quickly or vigorously with atmospheric moisture. Upon opening the desiccators, its contents get exposed to outside moisture. In that case, a glovebox or Schlenk-type apparatus may be more suitable for the purpose.
The most common desiccators found in laboratory are circular and made of heavy glass. It usually features a removable platform on which the items to be stored are kept. The desiccant, an inert solid such as silica gel, fills the space under the platform..