12-16-24W-36-46-56 43 inches 80/20 Bronze wound strings are often called old-school, vintage and/or bright bronze and were the most popular (only) alloy used to make acoustic strings until the introduction of phosphor in the early Seventies. 80/20 bronze wire is made from 80 percent copper and 20 percent zinc. 80/20 bronze provides balanced highs and lows with a slight increased in mid-range that seems to make the notes cut-through a little more. It took several years of trial and error to develop a proprietary string coating that resists tarnish and corrosion without compromising tonal quality.