In the United States, 360 Cookware manufactures a 4-quart slow cooker. What constitutes a large slow cooker is not well defined. However, a 4-quart model is generally considered of medium size, so as of February 2015, no widely available large slow cookers are made in the United States.
Slow cookers range from 1.5 quarts up to 10 quarts, with 4 to 7 quarts as the most frequently available sizes.
In the United States, 360 Cookware also manufactures a 2 1/3-quart slow cooker and a slow cooker base. The base allows the use of any correctly-sized pot as a slow cooker. The cooker base description on the company's website suggests use with the company's 2 1/3-quart saucepan or 4-quart stock pot. A division of Americraft, 360 Cookware manufactures cookware in West Bend, Wisconsin.
The majority of slow cookers are manufactured overseas, with most models sold under large brands, such as Crock-Pot, Cuisinart, KitchenAid and Hamilton Beach, made in China. Fagor slow cookers are made in Spain. Many of these and other companies originally manufactured slow cookers in the United States, and older models that were made in the United States can sometimes be found on online auction sites such as eBay.