Most large commercial extractors are radial and rely on the upward slope of the comb cells. When bees build their comb, the cells are sloped upward from the center rib at an angle of 10 to 14 degrees. By leveraging this slope angle, it is easier to extract the honey. In addition, the amount of work during extraction is reduced in the radial type because the frames do not have to be turned over to extract the honey from the other side of the comb (however some extractors are capable of turning combs automatically).