Bulletproof protective structure

A bulletproof structure comprising:

• a flexible base including intertwined or unidirectional ballistic fibers on which rigid metallic or ceramic elements are adhered adjacent to each other,
• wherein
• a face of said elements adhering to the fibers is a convex surface;
• the rigid elements adhere to the flexible base for a fraction of said convex surface;
• in a plan view the rigid elements have a polygonal or pseudo-polygonal shape, such that there are no voids between sides of two abutting rigid elements;
• a face of said rigid elements opposite to said convex surface is a concave surface having a radius of curvature that is lower than a radius of curvature of the convex surface so that a thickness at an edge of the element is between 0.5 and 2 mm greater than a thickness at a center of the same element.