What is this? Never seen it. It smells like incense.

Lu Banchi, also known as "Lu Banchi" and "Lu Banchi", is a measuring tool used in building houses, similar to the ruler used by craftsmen today. Lu Banchi, about 42.9 cm long, is said to have been written by Lu Gongyun class in the Spring and Autumn Period. Later, it was added to the geomantic circle to measure the good and bad luck of houses and houses, which was called "door plan". Also known as "square", it is mainly used to check whether the planed plates, purlins and structures are vertical and whether the edges are at right angles to each other. 1 city ruler =0.8 half a foot. Soon after, Lubanchi appeared, Ding Lan ruler was integrated, and then inches and centimeters were integrated. It is an important tool for measurement and calibration. Because of its special function, it is most widely displayed in geomantic culture and architectural culture.