A printing apparatus has a path for transporting flat items in the x-direction, and allows insertion and removal of a box-shaped module along the y-direction. The box-shaped module has a pressure device that exerts pressure in the z-direction on the flat items to be transported. The x-direction, y-direction and z-direction are orthogonal to one another. The components of the box-shaped module in combination with guides of the printing apparatus cooperate to initially move the pressure device along the z-direction during insertion of the box-shaped module into the printing apparatus and to move said box pressure device opposite along the z-direction upon reaching a predetermined position.