Round countertop warmers are used primarily to keep soups, stews, sauces and cheese dips warm until served. Most of the units are designed for wet operation. This means that a little bit of water needs to be dumped into the bottom before you place the insert inside. You will want to check to see if the insert and cover are included. Round countertop warmers need a separate insert placed in the cavity to actually hold the food. These inserts are not always included with the unit, but any standard size that matches the capacity indicated should work on models where the pan is not included. Another accessory that does not always come with the warmer is the lid. Lids are highly desirable because they help keep the food warm. The basic lids that do come with the units are either basic removable lids or ones that have a hinge.
Each warmer also comes with thermostatic temperature controls. The temperature will usually range up to 200 degrees or so, but there are no real temperature setting. Since hot food needs to be kept above 140° F for proper food safety, you will want to check the product temperature with a thermometer every two hours and adjust the knob if it falls below.