Intense Heat presents a new generation of polyester string. It is made of softened polyester material that does not have the rigid and stiff feeling of traditional polyester strings. This string is constructed by our newly developed nano-technology and creates a smooth surface that allows the string to move back to ist position rapidly during the competition. The result is excellent performance, control and durability. - No string movement, maximum power, superior durability and exceptional tension maintenance. Due to the super soft components, the string is much softer and arm-friendly than traditional polyester strings Gauge: 1.25 mm.