then. The silhouette has since been made a registered trademark with the U.S. Patent and Trademark Office. In 1997 the San Francisco Museum of Modern Art selected the KitchenAid stand mixer as an icon of American design. There is an attachment hub on the front of each mixer. Every KitchenAid mixer since the introduction of the Model "K" has allowed for cross-generational attachment compatibility, meaning that attachments from the 1930s can be used on modern mixers, and vice versa. This cross-generational compatibility extends only to attachments powered through the hub. Other accessories (beaters, bowls, etc.) are not necessarily compatible even across similar models in production at the same time (for example, not all current production six-quart bowl-lift mixers use the same accessories). Initially the mixers were only available in white; a range of four colors was introduced in 1955. Today, some KitchenAid products are manufactured in Ohio, South Carolina, Iowa, Mississippi, Indiana, Arkansas, Ontario, and Quebec while others are manufactured in China, and its appliances are distributed throughout North America. All KitchenAid stand mixers are assembled in its factory in Greenville, Ohio. The die-cast parts of the machines come from various manufacturing plants around the world. A factory tour, known as the "KitchenAid Experience" is conducted by the assembly line workers. Food and retail expansion In March 2016, KitchenAid announced that it would offer a line of food mixes with a Michigan food company, Franzese USA, Inc. In their press release, KitchenAid states, “Considering that tens of millions of American kitchens are outfitted with our stand mixers, we’re confident that these mixers will become a staple in many pantries.” References External links 1986 mergers and acquisitions Kitchenware brands Whirlpool Corporation brands Electronics companies established in 1919 Manufacturing companies established in 1919 American brands Home appliance manufacturers of the United States Kitchen knife brands