The Tecnifibre Black Code is a flexible and pliable string that allows the ball to dwell on the strings for longer and create extra spin and control. This unique string is made from third-generation polyester with a pentagonal cross-section and a co-polyester core for ultimate durability, making this string a fantastic, functional and hard-wearing string for all your needs. It offers a good bite on the ball resulting in better spin potential. The Tecnifibre Black Code String is a high-quality copolymer string that is designed to maximize power, reduce vibration, and increase spin produced. It is more tolerant making it at less risk of premature breakages from off-center hits due to wider sweet spot.