Centre pivot windows
are the most popular model in the market.
The sash rotates on a central pivot allowing ventilation through the bottom and the top; the sash can be locked in the ventilation position. It allows quick and easy cleaning of the outer pane.
A special clutch allows the sash to rotate smoothly
and to be set to the desired position even if it is windy, without the need for bolts; the clutch can be adjusted at will with a simple intervention.