Vacuum Insulated: Simple Modern Spirit tumblers are double walled and vacuum insulated, which keeps your favorite beverage hot or cold for hours Premium 18/8 Stainless Steel: Wine tumbler is made from high-quality, food-grade 18/8 stainless steel and is coated in a durable finish Premium Copper Coated Insulation Layer: The exterior of the inner wall, in the vacuum sealed area, is coated in a thin layer of copper for added insulation Clear Lid, No Closure: A push-in, clear plastic lid comes with each Spirit Wine Tumbler. This lid is made with Tritan™ by Eastman, which is BPA-free and dishwasher safe.