A window covering louvered blind system for horizontal and vertical orientations has a plurality of structurally sound and aesthetically appealing louvers within the body of the window-covering unit. A primary main body or middle segment of the louver is substantially planar with opposed fins that extend integrally in the same downward direction from the elongated edges of the main body at an obtuse angle. The preferred embodiments have a matching head-rail and bottom rail. Both symmetrical and asymmetrical versions of fins are disclosed. The louvers hereof are shown being used in blinds and shutters.