D'ADDARIO'S MOST POPULAR PURE NICKEL SET-. PURE NICKEL WRAP WIRE DELIVERS A WARMER, VINTAGE ELECTRIC GUITAR TONE. PURE NICKEL WRAP WIRE DELIVERS A WARMER, VINTAGE ELECTRIC GUITAR 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 .025, .035, .045.