Story of 'O' Rings are delightful decorations! The loop can be maneuvered to face forward or back. Great for die-hard fans of The Story of "O", must have sexslave jewellery! 6 Ring Sizes to choose from. Approximate Dimensions [Metric/US]: Internal Diameters Available: 14mm to 24mm [2mm increments] Sizing/Ordering ONLY in Metric Millimeters Width: 6mm [ 1/4" Inches] Diameter: [14mm] Diameter: [16mm] Diameter: [18mm] Diameter: [20mm] Diameter: [22mm] Diameter: [24mm]