The air flow direction of a single-layer louver air outlet is unidirectional, either horizontally left-right or vertically up-down. However, the air flow direction of a double-layer louver air outlet is bidirectional, featuring both horizontal left-right and vertical up-down directions.

Typically installed on pipelines or side walls as side supply air outlets. The double blade air outlet features two adjustable blades with different angles. The shorter blades are used to adjust the diffusion angle of the supply air stream and can also be used to change the direction of the airflow; while adjusting the longer blades allows the supply air stream to adhere to the ceiling or tilt at a certain angle (when supplying warm air). The outer blades of the double blade air outlet or the blades of a single blade air outlet can be parallel to either the long or short side, and the choice can be made according to the customer's requirements.