In general, the dart flight acts similar to an airplane’s wing; it adds stability of flight and lift to the back of the dart. By reducing the surface area of the flight (use a slim flight verses a standard flight), a player can raise or lower the back of the dart as it travels to the target. This produces a cleaner entry and less bounce outs. Unfortunately, it is usually thru trial and error that you can select a flight that is right for your game. The estimated surface area is shown under the product description.