This preformed Coconut Liner keeps your Window Box neat and tidy inside and connects it to nature outside. These Coco Liners create a down-to-earth feel and enhance the planters' connection with nature. They keep the aesthetic design of the planters from being spoiled by unsightly roots and dirt but still produce the effect of a natural growing environment. These preformed Coco-fiber liners are made to drop right into your existing 36" Window Box.