All Contessa Steel Picatinny Rails are precision made by Contessa Alessandro & C. s.n.c. The Picatinny rails are precision made to fit the rifle with exact hole spacing to screw to the rifle with the supplied screws and wrench. The Picatinny rails are available in 0, 10, 20 and 30 MOA, giving you more options for long range shooting. The Picatinny rings are made from steel, with blued or chrome finishes and available in a number of size options.