Yamaha Lower Unit Assy 6H3-45300-06-4D - Optimize your boat's performance with the Yamaha Lower Unit Assy 6H3-45300-06-4D. This robust lower unit assembly is engineered to deliver efficient power transfer, ensuring your vessel runs smoothly and reliably in various marine environments.. The Yamaha Lower Unit Assy 6H3-45300-06-4D is crafted from high-quality materials, providing superior durability and corrosion resistance. Its precise design ensures a perfect fit and straightforward installation, making it an excellent choice for both recreational and professional boaters.. This product has been superseded by: 6H3-45300-06-8D. 6H3-45300-06-4D - LOWER UNIT ASSY