ELECTRIC GUITAR STRING SET String Set for 7-String Electric Guitar XL Series nickel wound regular light (010 - 013 - 017 - 026 - 036 - 046 - 059) D'Addario XL Strings for Electric Guitar have been recognized worldwide as' 'The Guitarist's Choice' 'among guitarists of all genres and styles. XL strings are wound with great precision with nickel plated steel onto a hexagonal shaped core, resulting in strings with a distinctive, brilliant tone and excellent intonation.