All plastic bottles that are produced comply to the rules and regulations in this sector and have an identification code printed or embossed at their base, which indicates the material used in their production. The choice of material depends upon the application the plastic bottles and containers are intended to be used for. High density polyethylene is the most commonly used resin in the manufacturing of such products, due to the fact that this material is cost efficient, impact resistant and it is suitable for storing liquids, gels, oils or creams, being moisture and grease resistant. Low density polyethylene, although similar to high density polyethylene in composition, is preferred squeeze applications, since it is less rigid. Polyester, also known as PET, is the preferred material for manufacturing plastic bottles and containers that are intended for storing water, carbonated beverages or many types of foods, since it has good moisture and gas barrier properties. Polycarbonate is a transparent material that is mostly used for packaging water or milk. Polystyrene is used for manufacturing plastic bottles and containers for storing dry products like vitamins, medicines, petroleum jellies or different types of spices and condiments. Fluorine treated plastic bottles and containers have exceptional chemical barrier properties and are usually used for packaging different types of chemicals, insecticides, herbicides, pesticides, industrial cleaners, fragrances, essential oils, polishes, additives, gasoline based products and waxes, among others.