XL STRINGS D"Addario EXL117 Nickel Wound Electric Guitar Strings, Medium Top/Extra-Heavy Bottom, 11-56 EXL117 is an extreme hybrid set, optimally designed for tuning guitars down a whole step to D, while maintaining a comfortable playing tension like that of a "light" gauge set. Your Strings Matter. D"Addario"s XL Nickel Wound electric guitar strings are engineered to serve as the critical link between you and your guitar. XL"s are precision wound with highly magnetic nickel-plated steel to exacting specifications, resulting in strings with long lasting, distinctive bright tone, and excellent intonation. Ideal for the widest variety of guitars and musical styles, XL"s are the choice of countless professionals around the world. Alloys 101 - Your Tone Palette String alloys have a dramatic impact on your tone, feel and string life. D"Addario"s diverse selection of electric string alloys include: Nickel-plated Steel — Renowned for their distinctive, bright tone, XL nickel-plated steel is the industry standard for many genres and playing styles. Steel — Preferred by many rock, metal, country and jazz players for their super-bright, crunchy tone and highly textured feel. Pure Nickel — Containing lower magnetic properties than Nickel-plated Steel strings, Pure Nickel is the alloy preferred by many vintage enthusiasts. Choose Your Wrap Wire Round Wound — The most popular and universal construction, Round Wound strings deliver the traditional textured feel most players are familiar and comfortable with. Flat Wound — Offering a damped, mellow tone often preferred for jazz and twang, D"Addario Chromes utilize a flattened stainless steel "ribbon" wire polished to an ultra-smooth feel. Half Round - Delivering a smooth feel similar to flat wounds, D"Addario Half Rounds maintain the flexibility and tension of a round wound string. The D"Addario Difference It all starts with our exclusively engineered and built string winding machines. There is literally nothing like a D"Addario string machine. The combination of the most advanced computer-controlled winding technology and stringent incoming wire inspection delivers unmatched consistency, string after string, set after set. Every D"Addario string is made in the U.S.A., ensuring the highest quality and performance.