D'Addario J68 strings are designed specifically for baritone ukuleles. The 3rd and 4th string are a silver-plated copper wound on nylon complimented by a 1st and 2nd string which are made from our clear precision rectified nylon. Rectified nylons are created utilizing our proprietary center-less grinding technique which ensures that the roundness and dimension control of each string are of unsurpassed quality. This set is optimized for usage with standard DGBE tuning. Optimized for Baritone Ukuleles tuned to standard DGBE tuning Clear precision rectified nylon ensuring that the roundness and dimension control of each string are unsurpassed Preferred for their warm and long lasting tone Baritone Ukulele, Rectified Clear Nylon, Silver-Plated Copper Wound, 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