Wiwir Greenhouse Automatic Window Opener Solar Heat Sensitive Auto Vent Opener Automatic Roof Vent Opener Agricultural Greenhouse Window Lifter Autovent Kit Lifts 15 Lbs(Single Spring)

??Premium Quality?-- This Automatic Window Opener is made of quality built anodised aluminium.The paint spraying aluminum frame looks more lustrous, durable and rust-proof. ??Greenhouse Automatic Vent Opener?-- As the temperature changes,This auto thermo for window will automatically open and close your garden greenhouse vent to maintains the best growing temperature and prevents your greenhouse from overheating. ??Environmental friendly?-- Non electric, uses solar energy,open or close the greenhouse window as temperature rises or drops. This solar heat sensitive auto vent opener can lift up to 15 lbs. The cylinder closes well before deep freezing and opens again without problem. ??Working Conditions?--Start opening at 15°C-25°C (59-77°F);Fully open temperature at 30° (86°F) or above;Full opening distance :45 cm (18 inches).The greenhouse automatic roof vent opener kit will shut down completely when the temperature drops to bellow 59°F (15°C).Up to Load Capacity:7-15kgs(15-33lbs). ??Warm Tips?-- Do not use this automatic roof vent Opener lifts anywhere the temperature will exceed 45° (122F).