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.
The good news is that menstruation usually normalizes after about two years. Normal menstruation can last from one to eight days. For most women with regular menstrual cycles, their period will last for three to five days. That doesn't mean that anything is wrong if your period is longer or shorter. Period length can vary, and some lifestyle or medical changes may impact the duration or severity of bleeding and cramping.