Average fan

1 - To open

2 - To close

3   Installation of a stream of air up and down

4 - Installation of a stream of air to the left and to the right

Side fans

 1 - To open

2 - To close

  3 - Installation of a stream of air up and down

  4 - Installation of a stream of air to the left and to the right

Average fan

 1 - Vertical installation

2 - Horizontal installation