Foam peanut

Foam peanuts, also known as packing peanuts, styrofoam popcorn or packing noodles are a common loose-fill packaging and cushioning material used to prevent damage to fragile objects during shipping. They are shaped to interlock when compressed and free flow when not compressed. They are roughly the size and shape of an unshelled peanut and commonly made of expanded polystyrene foam. Two to three inches (50–75 mm) of peanuts are typically used for cushioning and void filling packaging applications.

Polystyrene foam peanuts

Polystyrene-based packing peanuts were developed and patented by Tektronix Inc. They were made commercially available circa 1965 by Dow Chemical. Originally made from 100% virgin polystyrene resin, peanuts made from 100% recycled polystyrene have been commercially available since the mid-90s. The color and shape sometimes indicate what it is made of and who made it. Often green is 70% or more recycled polystyrene, white is 70% or more virgin resin and pink means an antistatic agent has been applied; although there are some variations. The most common shapes are similar to a "S", "figure 8" or "W" . Foam peanuts are very light (usually around 3 grams per litre/0.17 to 0.2 lb per cu ft) and easy to use.