These ISAP ecOkay Compostable Pint to Rim Glasses CE 20oz / 570ml are made from a plant-derived plastic called PLA. Although PLA does not biodegrade fast enough in the natural environment to solve our litter problem, its key benefit is its plant-derived sustainability. These glasses are strong, clear, flexible, and highly comparable with glasses made from PET.Additionally, it is claimed that plant-based plastic has a 75% smaller CO2 footprint over traditional plastic over its whole life cycle. This means that, in places where recycling of traditional plastic is difficult, these plastic glasses are the better choice for the planet.