This OEM BMW M Performance exhaust clamp is necessary for installing your new M Performance exhaust system or for reverting back to your stock back box. With its 80mm diameter, this clamp is suitable for a range of N55 & B58 engine vehicles, including: M135i, M140i, 230i, M235i, M240i(x), M2, 330i(x), 335i(x), 340i, 340i(x), 430i(x), 435i(x), 440i(x) and many more.