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. This High-Strung Nashville Tuning gauge basically uses the octave strings from a 12-string set to give you a 12-string sound out of your 6-string guitar. Diameter Tension Item# Note inches mm lbs kg PL010 E 0.010 0.25 16.2 7.35 PL014 B 0.014 0.36 17.8 8.07 PL009 G 0.009 0.23 18.6 8.44 PL012 D 0.012 0.3 18.5 8.39 PL018 A 0.018 0.46 23.4 10.61 NW026 E 0.026 0.66 23.2 10.52