ConvaTec SUR-FIT Natura Two Piece Pre-Cut Stomahesive Skin Barrier with Tape Collar. Ideal for people whose stoma output is semi-formed to formed. The plastic coupling ring allows the pouch and skin barrier to snap together for audible security. This reliable skin barrier provides a unique formula that enables the skin barrier to adhere to both dry and moist skin. It is gentle on the skin yet holds firmly.