The wall surface is made of aluminum-plastic board. Don't think that aluminum-plastic board is inferior to you. In fact, aluminum-plastic board has many uses, such as colored solid color, imitation wood grain, and high-gloss. High-gloss aluminum-plastic board can almost replace black painted glass. Of course, the effect is not as good as that, but the cost is low. It is also too bad to buy cloth. Sometimes the cloth is easy to nest after stitching from the back. I make aluminum-plastic board.