Roll-out or pull-out mechanism for the transformation sofa beds. At the heart of his - a set of accessories consisting of roller bearings and metal hinges. For the transformation of a sofa bed in the position of "bed" to roll out ahead of the front section of the seat, while the back of the head restraint is put forward, and put the seat-cushion formed in the niche. "Telescope" allows you to get enough miniature sofa (assembled) dimensions, as the 2 / 3 "bed" is located in the seat and 1/3 - in the back. Advantages: cheap mechanism constructively width bed is not limited.