This vintage Purina "Cow Chow" milk scale is a highly collectible piece of early 20th-century agricultural advertising manufactured by John Chatillon & Sons. Engineered as a 30-pound brass spring balance, it was distributed by the Ralston Purina Company to dairy farmers as a functional tool to weigh individual milk yields and determine precise feed rations. The scale features beautifully preserved black lettering with the iconic slogans "Cow Chow Makes More Milk" and "Don't Guess — Use This Purina Milk Scale," [1] framed by the classic Purina checkerboard motif. Complete with its original dual pointer hands and bottom hanging hook, this solid brass artifact remains a sought-after piece of Americana for vintage farm, country store, and advertising memorabilia collectors.