Just installed a Truxedo Sentry CT on mine a few weeks ago. Roll-up aluminum with canvas covering. Very simple install with a little fidgeting to get it lined up even on both sides (loosened the clamps and adjusted by hand). Got it for $860.00 free shipping and a tailgate seal. Very happy with it so far. It can be removed if I need the whole bed relatively easy. Seems to be working in the late snows of Wyoming.