Volumetric flask
A volumetric flask (vol flask for short) is a type of laboratory glassware. It is used to hold and measure accurate amounts of liquid. It is shaped like a Florence flask, but has a flatter bottom. A volumetric flask has a tall, narrow neck with a stopper that can be used to close the opening at the top. There is a line on the neck to show how much to fill the flask. Volumetric flasks are made in many sizes, from a few milliliters to liters. They are often used to make liquid solutions. The neck is narrow to make measurements more exact when making a solution.