The most popular and economical type of FIBC liner is a lay flat tube. The liner lacks any curves or spouts. The liner typically has an open end and a heat-sealed end. Similar to how a form-fitting liner is inserted and affixed to a bulk bag, lay flat liners can also be used. Lay-Flat polyethylene liners are available either pre-installed in the bag or in rolls. They are Gusseted, available in clear or custom colours, have high strength and can be removed and reused