Suitable for trucks of different sizes, especially for cold storage and warehouses with large temperature differences between inside and outside. Started by an electric button, The expansion of the airbag makes the sealing effect excellent, and effectively prevents the convection of internal and external gas. The door seal adopts a high-quality air pump, and the inflation speed is fast, after the vehicle is parked, The blower starts to inflate, and the gap between the vehicle and the opening can be completely closed in a short time.