Hollister Adapt Convex Barrier Rings 13/16", 20 mm - sold by box of 10 Flexible, can be cut, bent, and stacked together to improve the fit of the skin barrier. Used to adjust skin barrier depth for deeper convexity. Creates a custom fit, including oval-shaped convexity. Helps to prevent skin erosion. Sold by box of 10. EachInner Diameter - 13/16" Style - can be stretched to 1"