A. Per the manufacturer, there is a line that is sometimes visible at the front of the seat, usually just to the left or right of center. This is known as the "mold line" or "seam line", where the liquid plastic molds (or "knits") together during the manufacturing process. The line is usually more noticeable in darker seats, and runs the length of the seating rim in that spot on the seat. It"s important to note that it is not a weak point in the seat and will be smooth to the touch.