1.This automatic window opener will efficiently open and close your greenhouse windows, allowing you to maintain optimal indoor temperatures. For results, we recommend purchasing two units. 2.Robust Construction: Featuring two powerful springs, this opener is designed for durability and can operate seamlessly using solar power, making it suitable for a wide range of greenhouse models. 3.Temperature Activation: The device responds to temperature changes in your greenhouse. It activates to start opening between 15°C and 23°C (59°F73°F), fully opens at 35°C (95°F) or higher, extends up to 45 cm (18 inches), and can support a maximum weight of 15 kg. 4.Simple Installation: Easily mount the opener on an aluminum frame or screw it into place. Comprehensive installation instructions are included, making it straightforward to set up and adjustable for various temperature settings. All necessary screws and accessories are provided, so please ensure everything is securely fastened.