Marlen Oval Convex All-Flexible Mounting Rings are designed for comfort and security. Made from soft and flexible neoprene rubber, these rings conform to your body for a comfortable fit. The oval convex shape is ideal for those with softer abdomens, stomas that sit level with the skin (flush stomas), or stomas located near the waistline where frequent bending is a concern. The gentle convexity of the ring helps keep your stoma secure within the opening, preventing it from retracting.