What do the codes on the bottom of plastic bottles mean?
The little recycle triangle on the bottom of most plastic containers and many other plastic is called an SPI code. This code was developed by the Society of the Plastics Industry (SPI) to help consumers and businesses to easily identify the resin type. This helps for recycling purposes but the code identifier is not meant to indicate that the material is “recyclable.” The industry chose to put symbols on the six most common resins plus an “other” category to capture the numerous other resins and the blends that are used.