SIDE RAIL AND OIL CONTROL RING COMPRISING SAME

A side rail forms an oil control ring together with a spacer expander, and includes: an outer peripheral surface; an inner peripheral surface having a vertically symmetrical shape in an axial cross section; a first side surface; and a second side surface. The inner peripheral surface includes an inner tip portion satisfying following Condition 1 in an axial cross section. 0.7≤R1/h0≤1.1In the expression, R1 represents a curvature radius (unit: mm) of a curve forming the inner tip portion, and h0 represents a height (unit: mm) of the side rail.