The Downtown is a briefcase that doubles as a pannier with QL-2 hooks.
The Ortlieb QL2 system allows fast and easy single-handed mounting and removal of the Downtown. Simply lift the top handle to remove the bag from the rack.
The same goes for attaching it: the QL2 hooks on the top of the bag can be slid forward and backwards, so that the bag can be positioned anywhere on the rack without requiring any tools. It is suitable for racks with a tube diameter up to 16 mm (hook inserts for diameters of 8 and 11 mm are included). We've never experienced or seen an Ortlieb pannier fall off a rack once its properly installed.
Made from Cordura and PVC-coated fabric, this bag will take years of abuse and be no worse for the wear.