S (Outer Diameter 155 mm, Inner Diameter 135 mm, Thickness Center 4 mm, Thickness End 8 mm), M (Outer Diameter 160 mm, Inner Diameter 145 mm, Thickness Center 4 mm, Thickness End 8 mm), L (Outer Diameter 170 mm, Inner Diameter 175 mm, Thickness Center 4 mm, Thickness End 8 mm)