The COLOP e-mark® GO ruler offers simple guidance in a straight line of the device. In addition, it allows printing on hard/uneven objects and on surfaces where sensor detection may cause problems, such as narrow edges. In addition, even small objects can now be printed with precise positioning. To facilitate particularly precise work, the Rule offers a recess on the side to allow the additional use of a conventional rule. This allows a definition to the nearest millimeter of distances between lines. Like the tape guide, the COLOP e-mark® GO ruler can also be used with consumables from the COLOP e-mark® product line. The Rule is particularly suited to the use of COLOP bracelets. e-mark®.