CONVEX All-Flexible Mounting Rings • For persons with fleshier abdomens and short or flush stomas. The 1/4" (6mm) convexity applies slight pressure to the stomal area, allowing the stoma to stay within the mounting ring opening and not retract Oval Convex • For stomas located close to the waistline where bending may be an important factor. 3-3/4" x 2-3/4" (9.5cm x 7.0cm) Part No. GN-60 Green Neoprene Rubber