The product is a self-teaching course designed for practical English language learning with a focus on effective speech. The 15-book set, published in 1938 by The Better-speech Institute of America, authored by Estelle B. Hunter, offers a comprehensive study guide for students looking to improve their language skills and speaking abilities. This textbook set, originating from the United States, provides valuable insights and exercises to help individuals enhance their English language proficiency in a self-paced learning environment.