The Mark Eden bust developer was a device and regimen sold by the Mark Eden company of San Francisco, California, that promised to enlarge a woman's breasts. Jack and Eileen Feather, California based figure salon entrepreneurs, were the promoters of the device. The product was widely marketed in women's magazines during the 1960s and 1970s, making claims such as, "For thousands, Mark Eden has transformed flat bustlines into firm, shapely fullness." Its makers withdrew the product from the market following their indictment for mail fraud.