Exaco Solar Powered Exhaust Fan System for ventilation even in greenhouses without electrical power.These are specially made for Exaco for greenhouses by a factory that has been producing attic exhaust fans for years that are reliable and sold through all major retailers. Available in two colors: Green and Black. For usage in a glass greenhouse,an optional Lexan panel is available to usetoreplace a panel of your tempered glass (which can't be cut). This is a very high quality clear piece of plastic that can be cut safely with a jigsaw to create an opening for an intake vent or exhaust fan. Kit includes: 50W solar panel 20 ft power cord (panel to fan) Brushless motor fan with louveredenclosure Case for two 12 volt back up batteries (batteries not included) Thermostat Optional: order a Lexan panel to replace one of the tempered glass panes of the greenhouse to allow for the exhaust fan to be installed. Lexan can be cut to fit, as needed. Specifications Solar Panel Specifications: Max Power ~50W Max Voltage 25.5 V Max Power Curent 1.97A Open Circuit Voltage 30.0V, short Circuit Current: 2.1A Panel Size: 29.5" x 20" x 1.5" CE approved Solar Panel Panel includes 20 ft power cord. Exhaust Fan Specifications: Brushless motor (lifetime guaranty) 12~26DC, 1000 RMP Fan size: 16" x 16" x 9" deep. CE Approved Exhaust Fan Battery Box Specifications: Holds two 12 volt batteries - batteries not included 9.25" x 6.25" x 4.25" Other Specifications: Total kit weight: 31 lbs Do-It-Yourself project Youwill have to buy standard 12-volt batteries Optional: Lexan panel to replace glass Brushless motor with LIFETIME warranty Installation Instruction Manual Warranty Lifetime warranty on brushless fan motor.