Elixir's 16540 3-Pack consists of 3 sets of Electric Nanoweb 9-42 (12002) strings. The Elixir 12002 Nanoweb Super Light string set for electric guitar consists of six extra supple strings. The wound strings feature a micro-thin Nanoweb coating that protects them from dirt and reduces corrosion. The unwound strings have had anti-rust treatment. As a result, these strings retain their clear sound and will last you three to five times longer than regular, untreated strings. The Elixir 12002 strings are made of steel and nickel-plated steel and provide the presence, punch and detail that you may expect from traditional electric guitar strings. If you are looking for sound and durability, go for these Elixir strings.