An annular air baffle disposed in a cavity of a rotatable gas turbine engine part includes an annular split ring supporting a plurality of circumferentially spaced apart fins. The cavity is closed at a radially outer diameter and open at a radially inner diameter of the part. The ring and the fins may be integrally formed in one piece. The fins may have common surfaces with the ring and the common surfaces may be circular cross-sectional surfaces of the ring and radially outer rounded corners of the fins. The fins may have triangular cross-sectional shapes with first, second, and third sides, rounded first radially inner corners between the first and second sides, rounded second radially inner corners between the second and third sides, and the radially outer rounded corners between the first and third sides. The fins may extend radially inwardly from the annular split ring.