Yamaha Lower Unit Assembly 66R-45300-12-4D - Enhance your outboard motor's efficiency with this genuine Yamaha lower unit assembly. Expertly engineered and crafted from premium materials, this assembly ensures exceptional durability and reliability in various marine environments. Its robust construction provides excellent resistance to wear and corrosion, guaranteeing smooth and long-lasting operation.. The Yamaha Lower Unit Assembly 66R-45300-12-4D delivers efficient power transfer and superior stability, improving your vessel's overall performance. Ideal for both professional and recreational boaters, this assembly helps maintain your outboard motor's peak efficiency. Trust Yamaha's dedication to quality and innovation to keep your marine engine running optimally, providing a dependable and exceptional boating experience every time you set sail.. This product has been superseded by: 66R-45300-12-8D. 66R-45300-12-4D - LOWER UNIT ASSY