An elastic layer includes a needle-shaped filler and a void and has a porosity of 20 vol % or more and 60 vol % or less. The elastic layer contains a first area and a second area. The first area extends from a surface of the elastic layer opposite to a surface facing the mandrel toward the mandrel and has a thickness of 30% of the thickness of the elastic layer. The second area is a central area in a thickness direction of the elastic layer and has a thickness of 40% of the thickness of the elastic layer. The needle-shaped filler in the second area has an orientation degree of 50% or lower. The needle-shaped filler in the first area has an orientation degree higher than that of the needle-shaped filler in the second area.