ECS Announces New Small Package SMD TCXO-2520. ECS Inc International, the world's leading private holding company, is a leader in meeting the growing global demand for high reliability innovation and Magnetics equipment. ECS Inc International is headquartered in the United States. We have about 100 joint sales offices and dozens of partners in more than 15 countries around the world. We have a world-class marketing, sales, distribution, engineering and customer service team working daily in the global technology network to focus on providing customers with the best solution.