An specialized piece of laboratory glassware used in iodine-based chemical reactions is the glass iodine flask. Usually conical in shape, the flask has a small neck and a glass stopper to ensure a tight seal. The flask is built to survive exposure to iodine and its compounds and is composed of sturdy, chemically-resistant glass.

The flask is frequently used to perform iodine-based processes and to store, mix, and dispense iodine. The flask’s volume varies, but it is usually small to hold the little amounts of iodine required in scientific investigations.