Features: This is a replacement cylinder for automatic window opener. High sensitive, automatic respond to weather changes, so you don't need to stay near the greenhouse. Non electric, uses solar energy, open or close the greenhouse vents as temperature rises or drops. Great for most greenhouse to open or close window automatically. Time and labor saving, also can supply a better temperature condition of plant's growth. Specifications: Condition: 100% Brand New Material: ABS Color: Black Temperature Range: 20~25℃ / 68~77℉ Size: approx. 33*1.5cm / 12.99*0.59in Weight: approx. 117g Package Included: 1 x Window Opener Cylinder Only Note: 1. Please allow 0-2cm error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. Features [Properties] This window opener sensor is a spare cylinder for automatic window openers, very practical. [Flexible performance] High sensitivity, can automatically respond to weather changes, so you don't need to stay near the greenhouse. [Efficient] Non-electricity, using solar energy, as the temperature increases or decreases, open or close the greenhouse vent. [Widely applicable] This window opener cylinder is very suitable for most greenhouses to automatically open or close window. [Time and labor saving] This automatic window opener sensor is very time-saving and labor-saving, and it can also provide better temperature conditions for plant growth.