It has several functions and advantages such as preventing the accumulation of dirt, dust, moisture and debris inside the hole, keeping it clean and protected from the weather. In addition, by covering the hole left by the ball, it prevents the accidental entry of foreign objects or the introduction of liquids into the coupling system. This helps ensure a secure and reliable connection when reinstalling the docking ball. It gives a cleaner and neater appearance to the tow hitch. This is especially beneficial when the vehicle is used without the trailer attached.