D'Addario EJ65S is an all-nylon set designed for use with soprano ukuleles. Each string is manufactured on D’Addario’s own advanced monofilament extrusion line built exclusively for the production of musical instrument strings. This set is optimized for usage with traditional ADF#B tuning. Each Custom Extruded Nylon sets are manufactured on D’Addario’s own advanced monofilament extrusion line built exclusively for the production of musical instrument strings. Each set features our exclusive laser sorted Pro-Arté clear nylon trebles for unsurpassed intonation with a warm, projecting acoustic tone. Optimized for Soprano Ukuleles tuned to traditional ADF#B tuning Pro-Arté Custom Extruded Nylon for highly accurate, laser sorted treble strings D'Addario's most popular ukulele set known for warm and long lasting tone Soprano Ukulele, Pro-Arté Custom Extruded Clear Nylon, Non-Ball End String Gauges: Nylon .024, .032, .034, .028 Made in the U.S.A. for the highest quality and performance