This wastegate fits the factory, 745i exhaust manifold. It is a completely rebuilt wastegate with all new parts except the cast iron base and valve which are remanufactured. The top end is all billet aluminum with a new, replaceable diaphragm nearly twice as large as the stock unit. Because it's always better to have two nipples, our wastegates feature dual chambers (upper and lower) and a fully adjustable spring bolt with lock nut. Although you should have enough range for just about any application, the spring is swappable. Fully rebuilt and shipped fully assembled. Documentation and installation instructions are included.