Abstract: Gratings for windows/doors, and more particularly window/door gratings which are structured with a plurality of integrally formed top members and a plurality of integrally formed bottom members. The top members each has a plurality of lower notches or cuts which can engage with corresponding upper notches or cuts on the bottom members and thereby enable the top members to easily, quickly, and firmly intersect with the bottom members to provide different patterns. The sections on the top and the bottom members between two notches or cuts may be of different shapes, such as, for example, a convexo-convex body with two concave horizontal surfaces.