Abstract: A printing cylinder having a longitudinal slot formed in the surface thereof to define at least one undercut surface against which both ends of a flexible printing plate are clamped to hold the plate securely against the surface of the cylinder. A plurality of individual cylinders is substantially evenly spaced along the length of said longitudinal slot. An individual biasing spring is disposed in operative compression between the bottom of the longitudinal slot, and a spring receiving opening in each of the cylinders urges individually each cylinder outwardly against the overlapping ends of the plate to hold them against the undercut surface. A spacer is secured to the bottom of the longitudinal slot, said spacer includes a plurality of evenly spaced protruding studs which receive the individual biasing spring to hold the spring at fixed locations.