The Santeco Kariba is a 350 ml double-wall vacuum-insulated tumbler, sized for a cup of coffee or tea on the way to work. It has a food-grade 18/8 stainless steel body with BPA-free parts, a transparent lid with a leak-resistant hinged cap and a wide mouth for easy filling and cleaning. The ergonomic shape gives a sure grip, it stays cool to the touch with hot drinks, and it fits most car cup holders. This one is Steel. Do not overfill, and do not put it in the dishwasher, microwave or freezer. Wash by hand with mild detergent.