Optimized for Soprano Ukuleles tuned to traditional ADF#B tuning- / Pro-Arté Custom Extruded Nylon for highly accurate, laser sorted treble strings / Soprano Ukulele, Pro-Arté Custom Extruded Clear Nylon, Non-Ball End / Made in the U.S.A. for the highest quality and performance / Environmentally friendly, corrosion resistant packaging for strings that are always fresh /