As the temperature changes automatically. The window opener maintains the best growing temperature and prevents your greenhouse from overheating. The window opener can be clamped onto or screwed onto your greenhouse frame. It is suitable for many greenhouses. The window opener is made of high materials. It is very safe and easy to install. The window opener is non electric, it uses solar energy to open or close the greenhouse vents as temperature rises or drops. Greenhouse vent automatic opener is ideal for your greenhouse window. It can be open and close your greenhouse window.