Ordered and installed a Bison Tri-Fold Hard Tonneau cover. Installs in minutes with six quick cam-lock plastic handle retainers. It seems solid and strong with aluminum honeycomb lining and powder coated steel panels top and bottom. It's not as sleek fitted as the ones with rails, but it costs half as much and does the same thing (more aerodynamic, keeps weather and nosey people out of the bed). I used some self adhesive foam pads under the retainers to prevent scratches to the painted surfaces and add a little give to the mounting points.