837898 Hy-C Company Inc SCADJ-S Shelter Black Steel Multi Fit Chimney Cover, Adjusts For 9 Sizes, Fully Assembled, Fits 8 x 8, 9 x 9, 8 x 12, 9 x 13, 12 x 12, 13 x 13, 8 Round Outer Diameter, 10 Round Outer Diameter, 12 Round Outer Diameter, Rectangular Or Round Chimneys.