Tianmen, also known as Tianguan and Shangsha, refers to the entrance of water flow in Dongtian, and the local households, also known as Wujiu, Earth Axis, Hand, Lower Arm, Xiasha and Xiaguan, refer to the exit of water flow in Dongtian. The direction that local households in Tianmen should point to in regulating qi and feng shui; The northwest belongs to Xu Hai in the earthly branch, and the southeast belongs to Tatsumi. Tianmen Dihu is more important in Feng Shui. It refers not to the direction, but to the place where hoses come and go.