For use in gear housings of all outboards. Do not mix with Quicksilver Hi Performance Gear lube or any other gear lubricants. Quicksilver Premium Gear Lube is an exclusive formulation engineered to provide excellent lubrication and corrosion protection to lower unit gears in high or low horsepower engines under varying operating conditions. It is recommended that you change your gear lube at least once per year, prior to storage, or after every 100 hours of operation under normal use or 50 hours for saltwater running. Refer to outboard owners manual