D'Addario's warm sounding, long-lasting phosphor bronze EJ42 Phosphor Bronze Resophonic String Set features color-coded ball ends. D'Addario is the world's largest manufacturer of strings for musical instruments. Many top guitarists won't play any other brand. Regardless of your playing style, D'Addario has a set of strings that's right for your resonator guitar. Gauges: 16-18-26-35-45-56.