The present invention relates to a flat-running device intended for equipping a mounted assembly without an air chamber for a motor vehicle, and to such a mounted assembly incorporating this device. The apparatuses of the present invention provide the medical practitioner with an improved tool for performing venipuncture methods. The distal tail includes a guidewire lumen that accommodates passage of a guidewire without threading the guidewire through the catheter tube. The drive motor causes rotation of the first wheel roller.