A1) 36 Diameter x H30 A2) 36 Diameter x H30 with 1-24" center fill B1) 42 Diameter x H30 B2) 42 Diameter x H30 with 1-24" center fill C1) 48 Diameter x H30 C2) 48 Diameter x H30 with 1-24" center fill D1) 54 Diameter x H30 D2) 54 Diameter x H30 with 1-24" center fill E1) 60 Diameter x H30 No extensions available on this option