The RetraxPRO MX retractable truck bed cover is part of our Premium Aluminum Series covers. Constructed from heavy-duty aluminum slats that are engineered to retract without trapping dust, wear out or freeze. Like the RetraxONE MX, the RetraxPRO MX has a sealed ball-bearing roller system that glides effortlessly along the rail with the convenient handle that eliminates the need for pull straps, Velcro, snaps or springs.