US Patent 7267617 Rail structure for pocket billiard table

A hollow rail structure directly extruded from aluminum in for pocket billiard table is disclosed to have an inner sidewall, an outer sidewall, a top wall, a bottom wall, ribs that define the inside space of the hollow rail into multiple compartments, a cover cloth locating groove longitudinally disposed on the top wall adjacent to the inner sidewall for the positioning of one side of a cover cloth, a longitudinal inside bottom channel longitudinally disposed inside the bottom wall adjacent to the inner sidewall for holding a wooden block for the mounting of the other side of the cover cloth and is fastened to the cover cloth locating groove, a longitudinal inside top channel formed inside the top wall, and a plurality of top locating holes in communication with the inside top channel and the outside space for the mounting of sights.