The Invincible Marine Lower Unit Lube Pump is designed to help you easily keep your boat engine properly lubricated so that it will continue to run smoothly. It's compatible with standard-sized quart bottles so that you can cleanly and easily transport the lubricant from the bottle to the engine. The marine pump fits domestic O/B and I/B motors, but adapters are available for imported motors. This pump already comes with an adapter for Yamaha and Tohatsu outboard motors for your convenience. The lower unit pump is designed specifically for outboard motors and is not suitable for use with other motors. It will help you to easily and cleanly keep your engine lubricated, which is an important aspect of engine health, so that your boat will run safely and smoothly during your ride.