Seal It Right, Keep It Tight. A reliable seal is the difference between smooth sailing and unexpected downtime. The Mercury Quad Ring (25-20295) is designed to keep cooling systems and critical engine components leak-free, ensuring your marine engine runs at peak efficiency. Unlike standard O-rings, this quad-ring design provides superior sealing, reducing wear and extending the life of your engine's vital systems.. Built for Performance. Engineered with high-quality materials to withstand extreme temperatures, pressure, and exposure to fuel and coolant.. Quad-ring profile offers a more secure seal than traditional O-rings, minimizing the risk of leaks in key areas.. Designed for exact fitment in select Mercury and MerCruiser engine models, eliminating guesswork during installation.. Where It's Used. Essential for cooling system maintenance, keeping fluid pathways properly sealed.. Ideal for engine overhauls, ensuring all seals are fresh and functioning at their best.. Compatible with