Abstract: An articulated oil-cooled piston for internal combustion engine extending along a longitudinal axis and including a piston skirt, a piston head with bosses, annular ribs and a piston pin disposed within the bosses for connecting the piston skirt and a connecting rod to the piston head. The piston head includes a ring belt which defines an outer border of an annular cooling oil duct. The annular cooling oil duct has a downwardly-facing opening which is covered by an annular plate. The annular plate is radially divided into plate parts, which are radially inserted into slots formed near the bottom end of the ring belt. When fully installed, the plate parts are disposed within a common plane which is oriented perpendicular to the piston axis.