EARTHWOOD SILK; STEEL REGULAR 80/20 BRONZE ACOUSTIC GUITAR STRINGS; 13-56 GAUGE; Ernie Ball Earthwood Silk; Steel Regular 80/20 Bronze acoustic guitar strings are made with; 80/20 bronze alloy wrap, along with; layer; silk between the wrap and steel core. The silk produces; more mellow sound and makes the string feel more comfortable while reducing finger noise. Gauges .013, .017, .026, .034, .046, .056;