Vilene Vliesofix Fusible Paperback Web
Vliesofix is a wonderful product for Applique.
It's very light weight which means you do need to stitch it down after ironing. Other wise during wash it could start lifting.
But the benefit for lightweight is that generally when you are appliqueing you have layers and they will still feel pretty pliable and easy to sew.
Where as when you use a heavier weighted product though you don't need to stitch it, it will be quite stiff and not very gentle on the machine needle.
Price given is per metre