The Mack Replacement Pipe is a practical and reliable solution for replacing the 4ME-21408 turbo adaptor in most DM Mack makes and models. With a 4" diameter and aluminized construction, this replacement pipe offers durability and a perfect fit. Sold individually, it is a cost-effective option that ensures optimal performance. Upgrade your vehicle's turbo system effortlessly with the Mack Replacement Pipe.