There are two types of Feng Shui rulers: Luban ruler and Jiutian Xuannv ruler. The total length of the Luban ruler is 50.4 centimeters, evenly divided into eight scales, namely wealth, disease, separation, justice, official, robbery, harm, and foundation. Among them, wealth, justice, official, and foundation are auspicious scales, and disease, separation, robbery, The harm is the size of the severity. Luban ruler was commonly used for doors in ancient times, and now it is more commonly used for doors, furniture, wood, stone, etc. Jiutian Xuannv ruler is mainly used for furniture.