Ervan vacuum-insulated water bottle is made from stainless steel and has a double-walled construction that creates a vacuum between the two walls. It also have LED temperature display is a device that is designed to provide information on the temperature of the water inside the bottle. It is typically used to ensure that the water is at a safe and comfortable drinking temperature. The display can be used to monitor the temperature of the water, as well as to indicate when the water is too hot or too cold.