SW-Motech PRO Rackpack tail bagPRO Rackpack tail bag The robust PRO Rackpack was developed specifically for use on racks and is a practical travel bag in combination with the shoulder strap. Combined with the luggage rack extension, it can be easily mounted on the STREET RACK or the ADVENTURE RACK as well as on standard carriers, passenger seat or a sissy bar. The extensions on both sides of the tail bag allow an expansion of the volume from 32 to 42 liters. In the two outer