String Fuel is a hybrid blend of refined naturally occurring oils that are speed blended with premium quality mineral oils to deliver a string cleaner & lubricant unlike any other. This proprietary formulation allows you to both clean & protect your strings to last longer and sound better while reducing finger noise and enhancing the speed you can slide your fingers. It’s silicone free & safe for any finish and even conditions unfinished fretboard wood. Includes the String Fuel solution impregnated in a no-mess ergonomic applicator and a lint free microfiber cloth that cleverly stores inside the applicator handle.