Abstract: The invention provides a system for stowing, employing a strap, which comprises an anchoring device at one end of the strap and a tightening device with a lever and automatic locking means at the other end of the strap, the tightener comprising a casing having an opening through which passes the strap, two hooks located on either side of the casing and adapted to be engaged against the respective uprights of the containers to be stowed, and a lever constituted of two parts, movable with respect to each other, the part comprising the free end of the lever being retractable after the strap has been tightened. This system is suitable for stowing roll-containers in delivery trucks or other means of transport.