D'ADDARIO'S BEST SELLING 7-STRING ELECTRIC GUITAR SET-. ROUND WOUND WITH NICKELPLATED STEEL FOR DISTINCTIVE BRIGHT TONE. ROUND WOUND WITH NICKELPLATED STEEL FOR DISTINCTIVE BRIGHT TONE. ENVIRONMENTALLY FRIENDLY, CORROSION RESISTANT PACKAGING FOR STRINGS THAT ARE ALWAYS FRESH. MADE IN THE U.S.A. FOR THE HIGHEST QUALITY AND PERFORMANCE. STRING GAUGES: PLAIN STEEL .010, .013, .017, NICKEL WOUND .026, .036, .046, .059.