This CDi Unit Assy 6AH-85540-00-00 is a perfect replacement for Yamaha Outboard 15HP 20HP. It is designed by C.D.I. brand which ensures durability and reliability. This item is suitable for those who own a boat and need to replace their outboard engine's ignition and starting system. It is compatible with various models and brands of outboard engines, including Yamaha. This item is easy to install and use, and comes with all the necessary components and accessories. If you're looking for a replacement for your outboard engine's ignition and starting system, this CDi Unit Assy 6AH-85540-00-00 is the perfect choice.