ConvaTec’s SUR-FIT Natura® ostomy system is a comprehensive product line with our latest skin barrier technologies. The plastic coupling ring allows the pouch and skin barrier to snap together for audible security. Only the SUR-FIT Natura® ostomy system is available with ConvaTec Moldable Technology™ skin barriers. These barriers hug the individual contours of your stoma to allow for a secure, personalized fit without the need for scissors. Pouch allows for draining.