Additionally, the Sonix FX's Kontour Yoke design allows for greater stability through reinforced stress points.
The [K] Sonix FX's Quad Shaft design enhances stability and weight distribution by way of four shafts connecting the handle to the head of the racquet as opposed to the traditional two. Its Karophite Black composition provides the Sonix FX with unparalleled frame stiffness and control due to Karophite Black's unique bonding properties. The Sonix FX's Kontour Yoke design also allows for greater stability and feel through the reinforcement of key stress areas.