The Roadworks 7 Inch Reduced To 5 Exhaust Elbow is a practical and reliable solution for Kenworth trucks with 45 inch boxes and single mufflers. Made of chrome plated steel, this exhaust elbow features a 7 inch diameter reduced to 5 inches, making it suitable for left and right side applications. It fits most Kenworth W900L trucks with 40 inch boxes and single mufflers, replacing the OEM part number K180-18616. With its durable construction and precise fit, this exhaust elbow ensures optimal performance and longevity for your vehicle.