The thermos is made of high-quality stainless steel. There is vacuum insulation between the walls of the thermos. The neck of the thermos is sealed by a screw-shaped cap, which is shaped for a smooth flow of the drink. The shape of the cap ensures easy opening/closing of the thermos. The outer side of the cup is made of stainless steel, the inner side is made of durable plastic. The system as a whole achieves excellent insulating properties. Keeps hot: 18 hours Keeps cold: 24 hours