Ultra-Pure Black Label "Classic" Valve Oil is a little thicker than standard valve oil and is designed for older horns with worn pistons or rotors. The thicker oil helps fill in the space between the valve and the casing and allows the valve to operate without any sticking. If you have an older instrument with worn valves, give Black Label "Classic" a try! USAGE INFO We recommend that you oil your valves at least once a week. Of course, the best results will be oiling each day since the oil will help wash down any contaminants. A freshly oiled horn feels great