What type of oil goes into a brandy warmer?

A brandy warmer typically uses a neutral oil, such as canola or vegetable oil, as it has a high smoke point and doesn't impart any strong flavors. Some people also use special lamp oil designed for warming beverages. It's important to avoid using oils with strong scents or flavors that could alter the taste of the brandy. Always ensure the oil is safe for use with an open flame.