Choose your sign! Our 30 oz. Stainless Steel Polar Camel Tumblers features double-wall vacuum insulation and include a clear lid. The mug has a narrower bottom to fit most standard cup holders. It is 2X heat & cold resistant compared to a normal tumblers. Polar CamelsThese travel tumblers are made from 18/8 guage stainless steel- also known as Type 304 Food Grade.