a traveller assembly for a linear guiding device includes a basic body supported on a guide rail assembly by at least one guide member unit , which is affixed to the basic body by a support member , the position of which along the basic body is adjustable . the guide member unit is adjustable relative to the basic body and the support member along a plane of advancement parallel to the guide axis of the guide rail assembly and in a direction perpendicular to the guide axis by an adjusting element that acts between the guide member unit and the support member .