Black Code from Tecnifibre is Tecnifibre's first geometric string offering durability and increased spin potential. Utilizing a co-polyester core, this string possesses excellent durability with greatly enhanced tension maintenance and feel. Black Code 16 features a pentagonal profile (5-sided), beneficial for generating more spin as it helps the string to bite into the ball. The string uses Tecnifibre's ThermoCore technology that promotes the following: 1. string to string friction is greatly reduce which enhances durability and 2. 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.