Unique Function Air guide groove: No longer need to worry about the bubble, even if the temperature is very high. Memory repair function: If the vinyl wrinkles up, a hair dryer and a board is enough to smooth it. What’s the difference between 3D, 4D, and 5D? 3D: It has stereo strips on its surface, give people a visual 3D feeling. However, the 3D strips couldn’t perfectly work under dark and strong light environment, and also easy to absorb dust and be broken. 4D: It changes the 3D strips inside the surface, which is a higher technology. This technology solves the dark light problem and makes the strips more stereo under street lamp.