Product Features:

1. Fully automatic greenhouse ventilation
2.Heat activated
3.Fully adjustable to open between 15-25 C (60-77 F)
4.Open window fully to 350mm
5.Suitable for windows up to 7kg
6.Easy fitting by clamps or screws provided
7. The manual of window opener
8.No batteries or electricity required
9. With the automatic window openers, you can be sure of an even temperature in your greenhouse day and night.they allow thermostatic ventilation control through the roof windows of your greenhouse.
10. Replacement cylinders are available.