GHS Infinity Bronze Acoustic Light Guitar Strings e. .012 .016 .024 .032 .042 .054 - set / Acoustic Guitar80/20 Bronze Roundwound,coatedLight TensionHexagonal CoreLonglife with Metal Surface TreatmentMade in USAExtended Performance Acoustic Guitar Strings. The GHS method to achieve extended performancestarts with high quality core and wrap wires for excellent tone, then utilizes a finely regulated coating method called MST (Metal Surface Treatment). This unique space age process coats the wrap wires for extended performance life with enhanced ton