Louver open-close : It is designed to decrease heat build-up in the buildings. Easy to use. The vents can be turned on-off and adjusted making ventilation easier. It has a secure locking system. Ventilation relies on natural air making it economical and decreasing electrical bills. Able to use on high places (with additional tools). Size: 1.50m width, 2.00m height, 0.055m (55 millimeters) deep.