Eco Fish Reusable Foldable Silicone Flip Straw Water Bottle 600ml. This product comes with a double ended silicone strap for securing the bottle when folded, and is only for this purpose. Do not use as a handle around the body of the bottle or around the screw top, as it is not designed for this and the screw top lid will not seal correctly with the loop around the screw thread.