A1) 48 Diameter x H30 A2) 48 Diameter x H30 with 1-24" center extensions A3) 48 Diameter x H30 with 2-18" center extensions A4) 48 Diameter x H30 with 8-8" perimeter extensions B1) 54 Diameter x H30 B2) 54 Diameter x H30 with 1-24" center extensions B3) 54 Diameter x H30 with 2-18" center extensions B4) 54 Diameter x H30 with 8-8" perimeter extensions C1) 60 Diameter x H30 C2) 60 Diameter x H30 with 1-24" center extensions C3) 60 Diameter x H30 with 2-18" center extensions C4) 60 Diameter x H30 with 8-8" perimeter extensions D1) 72 Diameter x H30 No extensions available on 72"