Hai (亥) Earthly Branch: element, zodiac, and hour
The Hai (亥) branch
The 亥 branch is associated with the Pig, the Water element, and the double hour around 21:00–22:59 local time. It appears in one of the four pillars of a BaZi chart.
Where it can appear
A 亥 branch can be the year, month, day, or hour branch of a chart. Each position changes how readers describe its influence.
The double hour
In the traditional twelvefold division of the day, the 亥 hour covers roughly 21:00–22:59 local time. Birth-time precision is required to confirm the hour branch.
Boundary
A Day Pillar is a calculated position inside a Four Pillars chart, not a verdict about a person. Read it with the Month Pillar, the visible elements, and the certainty of the birth record.