Royal Classics FL60B Flamenco Nylon Guitar String Basspak, High Tension Extend the life of your favorite string set with Royal Classics custom Basspaks. Royal Classics Flamenco Basses are bright, expressive, long lasting and tune up quickly. The Flamenco high tension Basspak is gauged.78mm/.031", .86mm/.034", 1.09mm/.043" and includes an extra #4 string. Treated with an ultra thin proprietary anti-oxidant coating. Crafted in Spain by and for serious guitarists.