The SHAMI EXHAUST FAN 24.5CM-8" Exhaust Fan Swift comes in two 8-inch sizes and is simple to install on glass in a circular opening from the inside. It is operated by string and has a back cover that can be closed. Circular opening size: 248–250 mm Delivery by air 5%±2200 Speedrpm 10%±384 Wattage of power source: 220V/50Hz 23