Roche-Thomas Premium line of lubricants are formulated and bottled in our facilities suing a special filtering process that eliminates impurities and residue. Our unique process insures that you receive a fast acting lubricant with a clean coat, virtually dust and lint free. Our premium key oil is a superior blend and won't harm your instrument. Key oil by design is a heavier oil then valve/slide oil, and is a clear oil with no dies or additives....