Abstract: A roll-up assembly for covering or uncovering an open container, such as a truck, includes a roll tube transversely extending over the container, a flexible cover being rolling about the roll tube whereby one end of the flexible cover is attached to the roll tube, a cross bar transversely extending over the container whereby the other end of the flexible cover interconnects to the cross bar, a flexible arm being integral with each end of cross bar whereby the flexible arm has a pivot point mounted on the side walls of the container, a pulley being disposed on the side walls of the container, a spool being connected to each end of the roll tube, a cable whereby one end of the cable is attached to the spool and the other end of the cable is attached to tension device for adjusting tension of the cable whereby the cable is looped around the pulley whereby the tension device is disposed on the side walls of the container, and a rotating device interconnected to one end of the roll tube rotating the roll tube so t