For your greenhouse window - automatically opens and closes your greenhouse window. As the temperature changes, it automatically maintains the best growing temperature and prevents your greenhouse from overheating. Non-electric, uses solar energy, opens or closes greenhouse vents based on temperature, including fittings and installation manual. Can be tightened or screwed onto your greenhouse. Important notice: Do not use this opener in areas where the temperature exceeds 50°C (120°F). Ensure your greenhouse window can be opened freely by at least 45 cm (18 inches). Do not apply excessive load by locking or covering the window. Do not disassemble the cylinder. The opener CANNOT be stopped manually. Greenhouse Window Opener Kit Color: silver black Material: aluminum alloy Fully adjustable between 20 and 25 °C Maximum window opening: 45 cm / 18 inches Size: 38 x 9.5 x 9.5 cm / 14.96 x 3.74 x 3.74 inches Package: 1 * Auto Window Opener Kit Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture to be slightly different from the real thing. The measurement allowed error is +/- 1-3 cm.