This product is made of foam material. Due to the difficulty in controlling the manufacturing process, some minor imperfections may occur, such as cracks, bubbles, dents, and peeling, especially at the seams, where gaps and white spots may appear. This is an unavoidable phenomenon during the foaming process air can escape from the edges, making it easier for small holes, gaps, and white spots to form. There is a small hole on the back because the foam is injected through this hole, hence the injection port.