The Koch Multi-Sak is an extended surface air filter designed for most medium and high efficiency air filtration systems. The Multi-Sak is capable of operating in systems with rated face velocities of 500 CFM to 3000 CFM. Available efficiencies range from 20% to 95%, and seven standard face sizes are offered. This broad spectrum of styles and models makes the Multi-Sak extremely versatile and suitable for almost any commercial or industrial air handling system. Multi-Sak filters are presently in use in over 20,000 applications, including hospitals, automotive plants, office buildings, universities, pharmaceutical facilities, and sports arenas around the world.