It is a general duct (material: wet carbon) developed to improve the cooling performance by adding a duct and obtain effective downforce. This product is a normal 3 ducts reverse type (duct shape is inside and shape with less outside protrusion). It is a general-purpose item that does not have to choose a car model, and install it in a bonnet or a fender, let it exhaust heat from this duct, increase cooling efficiency, and also cause down force by eliminating air pool. The shape is designed to fit various vehicles and it is designed to be slightly stretched, so it can be attached to loose curved surfaces. The rough size is 40 cm long x 20 cm wide, 2 left and right sets.