With offices in San Diego, California, specialty manufacturer Ozeri Corporation creates lifestyle products for the modern home. Concerned with environmental protection, the company offers solutions such as its 100 percent plant-derived dishware. Ozeri Corporation also maintains an interest in sustainable methods, plastic cleanup, and recycling. The seven different types of plastic in the world can be identified by locating a number on the plastic itself. PET, or polyester, is the first type, and it is known for its ability to keep oxygen out, which makes it good for food packaging. High-density polyethylene corresponds to number two; stronger and thicker, its uses include grocery bags and milk containers. Polyvinyl chloride, or PVC, has the number three stamped on it, and its main use is in toys, medical tubing, and cling wrap. Low-density polyethylene, the simplest form of plastic, uses number four and is found in grocery bags, plastic wrap, and other inexpensive materials. Polypropylene, or PP, indicated by a five, is mostly used in food containers, such as water bottles or thermoses, as it is much more resistant to temperatures than other types of plastic. Polystyrene, stamped with a six, is more commonly known as styrofoam. Any plastic displaying the number seven falls in the other category, which can include mixed and layered plastics.