A gas-liquid contacting tray suitable for horizontal mounting in a normally vertical column, which tray comprises a tray plate with substantially circular circumference and having top and bottom surfaces, which tray plate is provided with passages for gas between the bottom and the top surface, and on which tray plate two semi-circular tray sections are defined by a virtual diametrical line of the tray plate; and a total of three downcomers for guiding liquid from the top surface of the tray plate to below the tray, each downcomer extending from an inlet opening arranged in the tray plate to a downcomer outlet opening below the tray, wherein two of the downcomers are arranged in the corners of one of the semi-circular tray sections, and wherein the third downcomer is arranged on the other tray section substantially along a radius of the tray that is perpendicular to the diametrical line.