Retractable tonneau covers for trucks or Roll-n-Lock as they are also known are hard covers that as the name implies retract or roll instead of lifting them to gain access to the pick-up truck bed. These are great for truck owners that are constantly loading large or irregular shape cargo on their pick-up trucks and do not want to deal with the constant removal of the solid one piece cover. These covers are made of vinyl, ABS plastic or aluminium. They are easy to open, the cover rests on a tracking system or channel that is mounted on both sides of the truck.
The hard retractable tonneau covers are made of aluminium or ABS plastic and are constructed of individuals panels attached together that allows the cover to roll or retract into the mechanism installed at the front of the bed; similar to the roller shutter doors you may find in buildings; they are available with either a manual or electric mechanism roll or retract the cover. Aluminium retractable tonneau covers are generally finished with a black powder coat finish, vinyl or polymer coating or baked on enamel.
This is the most practical application of tonneau covers available for the working truck. Depending on your application you can get the vinyl cover which would be the least expensive of them and will protect your cargo from the elements, if you store materials in your truck or constantly leave it unattended when loaded a cover made of a hard material as ABS plastic or aluminium is your best option, with these covers you can secure and safeguard your cargo as they are equipped with locks and are not easy to break in to gain access to your cargo. Depending on manufacturer some covers are available with dual drain valves or channels to direct the water away from the cover to keep the interior of your trucks bed and its cargo dry such as the Ford Ranger tonneau covers.