Tri-Star has $400,000 in parts inventory! You read that right. $400,000 in Mercedes-Benz Parts in St. Louis. That means we have what your Mercedes-Benz needs. Tri-Star in St. Louis County specializes in Mercedes-Benz Factory-Certified Parts. Don't trust your vehicle with parts that may not have been designed for your vehicle. When you purchase parts from our dealership, you can rest assured that you are getting the highest quality parts from experts that know your vehicle.