Strings for acoustic guitar from the PRO series. They are made of Pro CTA Bronze 80/20 material, which is a mixture of copper and zinc. It is wound on a hexagonal core and delivers your guitar playing a brilliant live sound, deep bass and extremely clear treble. Strings have a special anti-corrosion surface that slows the oxidation. The thickness of the strings: .011, .015, .022, .032, .042, .052.