Elixir® Strings Acoustic Phosphor Bronze with NANOWEB Coating deliver distinctive phosphor bronze warmth and sparkle together with extended tone life. #1 acoustic guitar string* Only coated string brand to protect the entire string with an ultra-thin coating, keeping gunk out of the gaps between the windings Extended Tone Life – players report their tone lasts longer than any other string, uncoated or coated Consistent performance and tone – ready to play whenever you are Smooth feel that is easy on your fingers and enhances playability Reduces finger squeak – good for both performance and recording Anti-Rust Plated Plain Steel Strings resist tone-deadening corrosion, ensuring a longer life for entire set With less hassle and expense of frequent string changes, spend more time making music *Source: MI SalesTrak® (US $ Vol) - See more at: http://www.elixirstrings.com/guitar-strings/phosphor-bronze-guitar-strings.html#sthash.BA6NoZT8.dpuf