80/20 Bronze, commonly referred to as brass, is the original acoustic string alloy chosen by John D'Addario Sr. and John D'Angelico in the 1930s. 80/20 bronze strings are popular for their clear, deep, and penetrating tone in recordings, appealing to many traditionalists and vintage enthusiasts due to their historical significance. All D'Addario acoustic strings are wound on a hexagonal-shaped core made of high-carbon steel, resulting in a durable, bright sound with excellent intonation. D'Addario offers a complete range of acoustic guitar strings for all your replacement or customization needs. .024 gauge bronze-wound acoustic guitar string. Extra bright tone combined with deep and penetrating bass. Perfect as a replacement string or for creating custom sets. Made in the USA for the highest quality and performance.