Wyres optional P.T.F.E. (polymer tetra-fluoro-ethylene) coating is a proprietary process of combining a dry inert plastic with a carrying agent of rubbing alcohol. This light coating doesn’t dampen frequencies over the string, allowing more wire to contact . P.T.F.E. lubricates the string, protecting it against oils, acids and oxidation, resulting in less fret wear, less noise, longer life and a smooth, silky touch