The Yamaha Superior Synthetic Rotor Oil (40ml) is a specialized 100% synthetic lubricant designed specifically for the rotary valves of brass instruments like French horns, tubas, and trombones with F-attachments. Key Features Long-Lasting Performance: Unlike traditional mineral oils, the synthetic formula uses consistent molecule sizes that evaporate evenly, preventing the sticky feeling that occurs when lighter molecules in mineral oil evaporate faster. Corrosion Protection: It contains a powerful corrosion inhibitor that forms a long-lasting coating on rotor surfaces and casings to protect against rust and wear. Smooth Operation: Designed for optimum lubrication of rotor surfaces, it provides a quiet, fast, and silky-smooth valve action even during long playing sessions. Safety Design: The 40ml bottle features a child-resistant ca ...