Lab tubes are essential pieces of laboratory equipment used to store and transport liquids. They come in a variety of shapes and sizes, and are typically made of glass or plastic. Two common types of lab tubes are pipettes and pipets. Pipettes are 8-letter tubes with a narrow opening at one end and a wider opening at the other, allowing for precise measurements of liquid. Pipets are 6-letter tubes with a single opening at one end, and are used to transfer small amounts of liquid from one container to another.