Abstract: An integral monolithic strut for the rear brake of bicycles is described which comprises a one piece structure having a central portion of cubic shape through which an opening is caved out for the passage of the bolt which serves as support for the brake, the central portion extending in two lateral portions which have the shape of a truncated cone. The opening is sufficient to permit the complete insertion of a threaded bushing which has a handle bolt for fixing the screw which emerges from the body of the brake. The diameter of the opening is slightly greater than the diameter of the bushing, and the difference between the two diameters is sufficient for the insertion of a toothed disc which permits a perfect blocking of the body of the brake while the bushing is entirely fixed in the interior of the strut.