The Grand Rock Mack Replacement Pipe is designed to replace the Mack Part # 4ME-21783P2 specifically for MR Models. This replacement pipe is a practical and cost-effective solution for maintaining and repairing Mack vehicles. With its durable construction and precise fit, the Mack Replacement Pipe Replaces 4ME-21783P2, ensuring optimal performance and longevity for your vehicle. Whether for personal or commercial use, this replacement pipe offers a reliable and efficient solution for Mack truck owners.