Where is the Feng Shui Wall made and what is it made of?

The function of feng shui wall is to block evil spirits. First of all, we should know where the evil spirits are, not generalize. There are acupoints and shamanism in Feng Shui. There are also many forms of blocking evil spirits: for example, planting willows in front of the door and inserting mulberry in the back of the house. Most of the houses in the back belong to the north, and it is cloudy. Mulberry and elm trees can ward off evil spirits. According to the outdoor environment.