Inner surface made of high grade,double walled stainless steel with a a smooth, easy to clean finish. Inner & outer body made of high grade stainless steel , without any glass. Double wall stainless steel with vaccum insulation keeps contents cold/hot for hours. The easiest way to enjoy a beverage, anytime, anywhere. Hot & cold stain proof body coating. Usage Ideal for storing any beverage, offers convenience while travelling, fill the bottle completely to maintain temperature of beverage. Cleaning Instruction,use a mild detergent to clean the bottle. For best results,use a brush to clean on the inside.Bleach, chlorine,strong detergent or other such cleaners should not be used. When not in use, it is suggested that the lid be kept open to avoid odurs developing. Dish washer friendly.