??Safety Warning:This sticker on your door can let the rear of the vehicle notice that you are opening the door, acting as a safety warning. It is particularly important to improve vehicle identification capabilities and actively reduce accidents, especially for vehicles that park at intersections, turns and roadside. ??High Reflective: Our OPEN stickers are made of high quality PET material. The all-prism design makes it highly reflective, like a "luminous body". It can reflect light close to 180 degrees and emit a strong reflection effect, which greatly improves the safety when going out at night. ??Self-adhesive: The self-adhesive design can stick to your car body firmly and won't cause any damage to the car paint when you take it off. We recommend that you determine where you want to stick before sticking, then clean and dry the area. Gently press it down and stick it in one go without moving it repeatedly. ??Universal Size: Includes four 3.74 x 1 inch car stickers, a universal mini size for any car. This reflective sticker is perfect for doors and trunks and more. It can warn passing cars and pedestrians when parking and opening doors, making travel safer.