Double chain window actuators are suitable for up-hung, bottom-hung, horizontal pivot windows, and windows on point-supported glass curtain walls that are wider than 1.5 meters.It can be used to retrofit villa windows without affecting the original structure and decoration of the villa.Compact design, zinc alloy casing.Overload protection.he chain is made of special anti-corrosion materials (or stainless steel), making it suitable for long-term use in humid environment.The installation structure has three fixed points ensuring the most efficient distribution of force, which makes the installation easy and convenient.Less operation and maintenance costs are needed.Multiple options of opening stroke are available.Durability test guarantees more than 50,000 times of opening and closing movements.