The 20 oz. Mammoth Rover tumbler features double-walled vacuum insulation to keep ice for up to 36+ hours, and liquid hot 12+ hours. The Rover tumbler is built with durable 18/8 kitchen grade stainless steel. Featuring a clear lid, rubber gasket and stopper so your beverage will maintain constant temperature longer. Fits most cup holders. Lifetime warranty. While Supplies Last.