NIckel-plated steel on traditional roundcore;Significantly less tension, better flexibility and more sustain than hexcore strings with hexagonal core ;Optimal sound, easy to play, long sustain ;Roundcore strings must not be shortened before tensioning, otherwise the wrapping could come loose and the string becomes unusable. ;X50L Nickel Explosion .010-.046 light;Light .010 .013 .018 .026w .036w .046w;No single strings available!;