Fits BMW Stainless Muffler Apexi N1 Type 4" Flat Tip & Silencer CFDue to the overwhelming popularity and benchmark standard of the N1 Style Mufflers it was only natural that this muffler was offered as a universal. Now, the N1 style muffler can be enjoyed on virtually any vehicle. Similar to the cat back system, the N1 style universal uses premium polished SUS 304 stainless steel constructed using both robotic and hand crafted welding. Straight through design ensures maximum power on properly tuned exhaust systems.