All Pro-Arte treble strings are measured by a sophisticated computer controlled laser which performs consistency and quality checks, insuring true sounding trebles in every set. Bass strings are made from Silverplated Copper wound on Nylon. D’Addario is the world’s largest manufacturer of strings for musical instruments. Regardless of your playing style, D’Addario has a set that’s right for you. EJ46 Acoustic Guitar Strings have gauges 28-32-41-30-36-44.