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 Compact Convex • For the smaller person with a well-positioned stoma. 3-3/4" x 3-1/8" (9.5cm x 7.9cm) Part No. GN-102 Green Neoprene Rubber