Opsite Flexifix Gentle ~ 2.5cmx5m. OPSITE Flexifix Film is a transparent, adhesive film. The film is moisture vapour permeable, conformable and extensible. It is widely used to provide a moist wound environment for superficial wounds; it is also ideal for use as a secondary dressing.. Benefits:. To retain Primary dressings. To protect the skin around stoma and under leg bag.