It is aftermarket replacement parts fit for carburetor air filter mouth size 50mm / 1.97inch. Made of high quality lightweight aluminum alloy material, durable and long time for use. Perfect fit, easy to install and use. This velocity stack has a smooth funnel shaped inlet to help airflow and improving your motorcycle work performance. A variety of colors are available,Please confirm the size and compatibility of the product before purchasing. Package includes:1 x Motorcycle Velocity Stack With Monuting Screws. 1