Dodge Gen 3 Hemi flow pipe is 11″ length and 1.875″O.D.” Tig welded flange with gloss black finish. Fits cylinder heads casting # 53021616BA with square exhaust port. By testing your exhaust port with and without a pipe you will know how it effects the flow positively or negatively. Flow pipe improves flow roughly 5 percent over an exhaust port with no pipe. Mounting hardware included. Please e-mail with questions.