D'Addario XL Nickel Wound Electric Guitar strings are world-renowned as "The Player's Choice" amongst players of all genres and styles. XL's are precision wound with nickelplated steel on a hex-shaped core, resulting in strings with a distinctive bright tone and excellent intonation. XL145's are specially designed for players who prefer a heavier gauge, but want an unwound G - perfect to drop tuning to E-flat or D.