The Vaico Secondary Air Injection Hose (525i 530i) - V201573 is a high-quality replacement hose designed for use in BMW 525i and 530i models. This hose is responsible for delivering secondary air to the engine, helping to reduce emissions and improve overall performance. It is made from durable materials and is designed to meet or exceed OEM specifications. This product is easy to install and is a cost-effective solution for maintaining the proper functioning of your vehicle's secondary air injection system.