The Model OD-11 is a variable air pattern swirl diffuser having a set of movable inner vanes to alter the angle of discharge from horizontal to vertical, which is imperative to ensure optimum heating and cooling function. By regulating the inner vanes, varying throw discharges can be achieved from fully horizontal to vertical projection, which is important in the heating mode. To accomplish this adjustment two types of control are offered, manual or electric motor operation. Supplied with a circular outer tube casing having a flush flange and a set of movable inner vanes. Typical applications include shopping malls, exhibition halls and other large open spaces with mounting heights of between 3 m to 12m, where large air volumes and temperature differentials are required.