It has strong ventilation because it upgrade fully closed pure copper motor offers fast fume suction, ventilation, keeping the indoor air clean and comfortable.It has seven thickened blades deliver more powerful and uniform air volume, not easy to deform. It runs stably and vibration-free, ensuring large air volume while reducing noise.It is constructed of iron material.There are several sizes for your choice: 6inch, 4Inch, 7inch. Easy to install, suitable for kitchen, toilet, office, meeting room, restaurant, supermarket, cinema, Internet cafe, workshop, waiting hall, etc.Item Name: Exhaust FanMaterial: IronFeatures: Bass Noise Cancellation, Strong Wind, Super Suction Voltage: 22VFrequency: 50 HzSize Details:4Inch Black, Diameter: 10cm or 3.94" (Approx.)4Inch Black, Length: 7.3cm or 2.87" (Approx.)6inch Black, Diameter: 15cm or 5.91" (Approx.)6inch Black, Length: 15cm or 5.91" (Approx.)7inch Black, Diameter: 18cm or 7.09" (Approx.)7inch Black, Length: 14cm or 5.51" (Approx.)4Inch White, Diameter: 10cm or 3.94" (Approx.)4Inch White, Length: 7.3cm or 2.87" (Approx.)6inch White, Diameter: 15cm or 5.91" (Approx.)6inch White, Length: 15cm or 5.91" (Approx.)7inch White, Diameter: 18cm or 7.09" (Approx.)7inch White, Length: 14cm or 5.51" (Approx.)Notes:Due to the light and screen setting difference, the item's color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x Exhaust Fan