D Addario s most popular acoustic set EJ16 delivers the ideal balance of volume projection and comfortable playability. Phosphor Bronze was introduced to string making by D Addario in 1974 and has become synonymous with warm bright and well balanced acoustic tone. D Addario Phosphor Bronze strings are precision wound with corrosion resistant phosphor bronze onto a carefully drawn hexagonally shaped high carbon steel core. The result is long lasting bright sounding tone with excellent intonation. Also available in 3D packs