Clear Plastic Tube. A clear tube is a tube made of plastic with a transparent or translucent body. The body may be of a solid or hollow construction, and it may be made from either a homogeneous or a heterogeneous material. Clear tubes may have a smooth surface, or they may have a surface treatment to improve their appearance, such as a decorative coating. They may also have a diameter of less than or equal to 100 millimetres, or they may have a diameter of greater than 100 millimetres.