What do Mitsubishi elevators 620 and 600 mean?

The ghost story of Lv Gong's daughter: Like a song weeping like a glue painting like a dream, telling the truth is empty. Who communicated the dark road, who knocked down the barrier of life and death. Hold the first moon, gently enjoy the breeze, peaches and plums are silent, and the night is silent. Don't ask, human love, emotional blending, ghost infatuation, spiritual impact. Don't be tender, you can shake the earth.