Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. 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 Feather, a California based figure salon entrepreneur, was the promoter 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.