Plastic rocks glasses, made of high quality, break-resistant plastic, can hold between 5 to 10 ounces of mixed drinks served over ice. Also known as an old-fashioned glass, our selection from GET Enterprises and Thunder Group made of SAN plastic or polycarbonate, has a heavy base and feels sturdy when holding on to your favorite drink. Dishwasher safe and safe to use, these plastic rocks glasses are especially popular at catered events and outdoor bbqs.