Classic N Series characteristics: clear, warm sounding, heavy duty construction "Classic N Series SUPERLONA are heavy duty nylon strings. The basses E, A, d are silverplated copper round wound on chrome steel flat wound. The treble strings are made of selected nylon. Classic N Series SUPERLONA are easy to play and give the player a budget series of high quality guitar strings. 1st E Plain Nylon .027" 15.1 tension lbs 2nd B Plain Nylon .031" 12.2 3rd G Plain Nylon .039" 12.3 4th D Silverplated Copper Round Wound .030" 14.7 5th A Silverplated Copper Round Wound .035" 14.2 6th E Silverplated Copper Round Wound .043" 13.5