Features: Prevent greenhouse overheating. Ideal for your greenhouse window: open and close your greenhouse window. As the temperature changes automatically, it maintains the best growing temperature and prevents your greenhouse overheats. Non-electric, uses solar energy, opens or closes greenhouse vents as the temperature rises or falls. Can be fastened or bolted to the frame of your greenhouse. Specifications: Kit greenhouse window opening Material: aluminum alloy Fully adjustable between 20 and 25 ° C (68 and 77 ° F) Maximum window opening: 45 cm / 18 inch Maximum opening weight: 7 kg / 15 lb Size: 38 x 9.5 x 9.5 cm / 14.96 x 3.74 x 3.74 inch (approx.) Package : 1 x Automatic Window Opener Kit Notes: Do not use this opener anywhere where the temperature exceeds 50 ° (122F) Make sure to that your greenhouse window can be freely opened at least 18 "(45 cm) Do not apply excessive loads blocking or covering the window Do not disassemble the cylinder Opener CANNOT be stopped manually Monitors not calibrated the same, item color shown on the Photos may be showing slightly different from the real object. Please take the real one as standard.