Elixir Strings Nanoweb 80/20 Bronze Acoustic Guitar Strings -.010-.047 & .010-.027 12-String Light12 string acoustic guitar strings constructed with 80 20 (80% copper, 20% zinc) bronze wrap wire Played for a bright tone with an expressive, vibrant presence NANOWEB Coating provides a smooth feel Our coating technology protects against common corrosion and debris buildup, extending tone life longer than any other brands coated or uncoated strings (Elixir Strings player survey) America's #1 acoustic guitar string brand (MI SalesTrak US $ Vol) 12