Clean oil is the foundation of a reliable, high-performing outboard, and the Mercury Outboard Oil Filter (35-877761K01) 4-Pack ensures your engine gets the protection it needs. Designed for 75-150 HP Mercury FourStroke models, this filter captures harmful contaminants before they can cause wear, keeping oil circulating smoothly and extending engine life. With four filters in one pack, routine maintenance is simple, and you'll always have a spare when it's time for a change.. Built for Engine Protection. High-Efficiency Filtration - Traps microscopic particles that could lead to sludge buildup, helping to maintain cleaner oil for longer.. Anti-Drain Back Valve - Prevents dry starts by retaining oil in the filter when the engine is off, ensuring immediate lubrication upon startup.. Corrosion-Resistant Housing - Electroplated construction holds up against saltwater and harsh marine conditions, preventing rust and degradation.. Smart Maintenance for Uninterrupted Performance. Regular oil c