D'Addario EZ900 85/15 Bronze Acoustic Guitar Strings Extra Light - 10-50Combines 80 20 bronze with the longer life characteristics of Phosphor Bronze, delivering a bright tone that accommodates a variety of musical styles. The 85 15 Bronze wrap wire is precision wound onto a carefully drawn, hexagonally shaped high carbon steel core, resulting in long lasting, bright sounding tone with excellent intonation, perfect for any level of acoustic player.