The guide body consists of an aluminium square profile with lateral, parallel, form-fit, internal hardened steel rods. Two guide carriages, each with its own drive, move along the guide body. The timing belt is guided within the profile, so that it is independent of the mounting position. Due to the high rectangular profile high torques and loads can be taken up. In addition, a very high stability is ensured for long axis systems. The toothed pulleys have maintenance-free ball bearings. The belt tension can be easily readjusted via a tensioning device within the carriage. This device also helps to adjust the symmetry of the carriages in applications where two parallel linear units are used.