1. Revolution TWO PIECE design, can be packed in cartons for effective warehouse storage and sea shipment. 2. Strong, lightweight injected moulded ABS ,integrate with all types of flexible ductwork 3. Easy to handle with no sharp edges and manufactured from corrosion free material, they are perfect for both commercial and domestic applications 4. Can be regulated by the installation of optional Motorized damper 5. Available as insulated or plain model. High quality Aluminum and XPE foam insulation 6. Fast and easy installation