above the luban ruler is the door ruler, below is the ding lan ruler, the door ruler is used for the construction of the yang house, for the measurement of the living people's house construction and household appliances, and the ding lan ruler is used to measure the yin house, the ancestral tablet, the red marked on the ruler is auspicious, the black is fierce, according to the measurement of the size of the thing to find the meaning of the word marked on it.

precautions for using the door meter:

1, generally when measuring things, you must choose auspicious red characters.

2, the head of the money belongs, when carefully measured.

3. the red characters between the money books are auspicious.

4. the righteous gate is used in temples, taoist temples, schools and other places for religious education, and the residential gate should not use the word righteous in vain to avoid disaster.

5. the divine position and the buddha's tools are also measured by the door meter, and cai or this character should be used.

6, the general yang house to take if you can yin and yang of course the best degree, but in general, it is best to take the red character between the money and the present.