WIDE COMPATIBILITY: This carburetor is designed for Stihl FS38, FS45, FS46, FS55 2-mix series mowers, and is perfectly compatible with model 4140 120 0623. EFFICIENT FUEL MIXING: Adopting advanced fuel mixing technology, this carburetor is able to precisely control the mixing ratio of fuel and air to ensure efficient fuel combustion. Excellent performance improvement: The performance of Stihl FS38, FS45, FS46, FS55 2-mix mowers will be significantly improved after adapting this carburetor. Whether in terms of start-up speed, cutting efficiency or overall operational stability, the machines will demonstrate excellent performance, helping users tackle a wide range of mowing tasks with ease. Convenient installation and maintenance: The carburetor has been designed with user convenience in mind, and the installation process is simple and intuitive. This makes maintenance and operation of the mower easier and improves work efficiency. DURABLE: Made from high-quality materials, this carburetor features durability and excellent stability. It maintains stable performance even under harsh working conditions, reducing the risk of malfunction and damage. Users can count on long-lasting, reliable operation without frequent replacement or repair. "