An anti-rolling device for cylindrical containers, such as mailing tubes, has a stabilizing member with an internal aperture for inserting over a portion of the container. The rate conversion control section includes a first rate converter, a second rate converter, a data rate conversion section, and a data output section. The saddle-shaped support has a circulating traction mechanism and driving members connected to the circulating traction mechanism. An engine frame for mounting an engine are connected with a pair of right and left vehicle frames, and a transmission case is placed between rear portions of the right and left vehicle frames.