Up To Date 42+ Elixer 12 String Acoustic Guitar Strings. These last a long time. Standard acoustic 12 strings guitar tuner 📟 / guitabs tuners 🎸. Enjoy the lowest prices and best selection of elixir 12 string sets for acoustic guitar at guitar center. Elixir strings are excellent to use, they sound very good they stay in tune and they last a lot longer than any other strings out there.