An apparatus for positioning and aligning one or more pre-punched printing plates on an imaging cylinder comprising: an imaging cylinder for a computer-to-plate imaging device, the cylinder being rotatable around an axis, the rotation defining a circumferential direction, the axis defining an axial direction, the cylinder having a base body and an outer surface; and a registration device connectable to the base body of the cylinder and when connected having an outer surface forming part of the outer-surface of the cylinder, the registration device arranged to position and align one or more pre-punched printing plates on the outer surface of the cylinder, wherein the registration device when connected includes: a groove extending axially on the outer surface of the cylinder, and forming a gap on the outer surface of the cylinder, a first register pin having a fixed position on the base body of the cylinder, and a second register pin movable in the groove and after being moved to a next position on the base body of the cylinder, being fixable to the next position, characterised in that the first register pin is insertable into a first hole of a printing plate to provide a starting point for the plate, and the second register pin is insertable into a second hole of the plate when the first register pin is inserted into the first hole, the second hole being at a plate position dependent on the width of the plate and defining, when the first register pin is inserted into the first hole and connected to the fixed position, a second position in the axial direction on the outer surface of the cylinder, the second register pin being insertable into the second hole after being moved to the second position, and being fixable to the second position to position the plate on the outer surface of the cylinder. an imaging cylinder for a computer-to-plate imaging device, the cylinder being rotatable around an axis, the rotation defining a circumferential direction, the axis defining an axial direction, the cylinder having a base body and an outer surface; and a registration device connectable to the base body of the cylinder and when connected having an outer surface forming part of the outer-surface of the cylinder, the registration device arranged to position and align one or more pre-punched printing plates on the outer surface of the cylinder, wherein the registration device when connected includes: a groove extending axially on the outer surface of the cylinder, and forming a gap on the outer surface of the cylinder, a first register pin having a fixed position on the base body of the cylinder, and a second register pin movable in the groove and after being moved to a next position on the base body of the cylinder, being fixable to the next position, characterised in that the first register pin is insertable into a first hole of a printing plate to provide a starting point for the plate, and the second register pin is insertable into a second hole of the plate when the first register pin is inserted into the first hole, the second hole being at a plate position dependent on the width of the plate and defining, when the first register pin is inserted into the first hole and connected to the fixed position, a second position in the axial direction on the outer surface of the cylinder, the second register pin being insertable into the second hole after being moved to the second position, and being fixable to the second position to position the plate on the outer surface of the cylinder. a groove extending axially on the outer surface of the cylinder, and forming a gap on the outer surface of the cylinder, a first register pin having a fixed position on the base body of the cylinder, and a second register pin movable in the groove and after being moved to a next position on the base body of the cylinder, being fixable to the next position, characterised in that the first register pin is insertable into a first hole of a printing plate to provide a starting point for the plate, and the second register pin is insertable into a second hole of the plate when the first register pin is inserted into the first hole, the second hole being at a plate position dependent on the width of the plate and defining, when the first register pin is inserted into the first hole and connected to the fixed position, a second position in the axial direction on the outer surface of the cylinder, the second register pin being insertable into the second hole after being moved to the second position, and being fixable to the second position to position the plate on the outer surface of the cylinder.