Tecnifibre Black Code is a Co-Poly string and features Thermocore technology. It offers a pentagonal profile for good bite on the ball resulting in better spin potential. This string has minimal tension loss while offering an extremely soft feel. String to string friction is greatly reduce, enhancing durability and further promoting spin and ease of stringing. The ThermoCore technology also gives the string greater flexibility for more power and a softer feel. An excellent choice from all areas of the court with enhanced spin, good power, and a softer feel.