The quality of an eraser and the use of the right eraser are crucial for optimum results. Basically, two different materials are used to make erasers: Rubber and plastic. All rubber erasers and the majority of plastic erasers manufactured by Faber-Castell are PVC-free. Faber-Castell's PVC-free erasers do not contain harmful phthalate plasticisers. Phthalates have been reported to cause several undesirable effects when in contact with the human body. The balanced plastic mixture ensures smooth and smear-free erasing.