In the case of the B (or center) pillar on four-door sedans, the pillar is typically a closed steel structure welded at the bottom to the car's rocker panel and floorpan, as well as on the top to the roof rail or panel.
On an average a period lasts between 3 to 5 days. It is normal for a girl to have irregular periods in the beginning. During this time, the duration of her periods may vary from as short as 2 days to as long as 7 days. It can take up to a year for periods to become regular.
How long will my first period last? When your first period arrives it might not last very long, as it can take your body some months to get into a regular pattern. As a general rule, once they're settled, you'll have a period every 28 to 30 days and it will last three to seven days. It might seem a lot, but it's only about three to five tablespoons.