febi 49371 Idler Pulley for auxiliary belt, with bolt suitable for Mercedes-Benz. Belt drives have the task of transmitting and driving the rotary motion of the crankshaft to the engine control system or to the auxiliary units. Belt drive components are therefore required to deliver maximum performance in every vehicle. The idler pulleys guide and hold the auxiliary belt in its entangled position which is why they are also called guide pulleys. febi offers a comprehensive range of idler pulleys for auxiliary belts in OE matching quality. Idler pulleys from febi are intensively tested. Our quality management tests the offered idler pulleys for various requirements and loads, e.g. accuracy of fit, dimensional accuracy, material quality, and tensile strength. When replacing the auxiliary belt, the surrounding components should also be checked for wear. For all parts to work together perfectly, it is extremely important that they are precise and made of high-quality materials. febi offers complete auxiliary belt kits for certain vehicle types which contain all the individual parts required for professional replacement.