The EXL115BT Medium Electric Guitar Strings are part of the D'Addario Balanced Tension Series that are comprised of mathematically optimized string gauge combinations, resulting in greater control and playing comfort. Combined with the distinctive bright tone of XL nickel wound strings, each set offers greater dynamic control and a more consistent feel between strings for evenly balanced bending, strumming, fretting, picking, plucking and slapping. EXL115BT gauges range from 11-50.