D'Addario EXL120-E Bonus Pack: Super Light Electric Guitar Strings 10 Pack with 10 Bonus High E Strings (9-42) Pack of 10 super light gauges for maximum flexibility and biting tone Round wound with nickel-plated 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 XL guitar strings are wound with nickel-plated steel, known for its distinctive bright tone and excellent intonation