By choosing Coway water filters, we chose a manufacturer that develops and manufactures its products in-house. Furthermore, Coway uses only the highest quality materials and has its devices independently certified. Its in-house Research & Development Center, operated in cooperation with Seoul National University, ensures that its devices are always based on the latest findings. This means the entire quality assurance process is handled by one company—the manufacturer in Korea. This convinced us! Just like Coway, we work every day to contribute to a healthy, hydrated life for our customers.