An improved retainer system allowing reliable strapping of a package while incurring only minimized wear. An additional retainer device (17) is placed in front of the inner side of the strap guide frame (11) and comprises an elastic, longitudinally stretching element (18, 19) and a mating support (30). The elastic element and mating support are made of a low-wear material relative to the strap and are mutually parallel, as well as parallel to the strap outlet aperture (23). The elastic element and the mating support together subtend a gap through which the strap is pulled.