This racket series stands for speed Compatible with the Sony Smart Tennis Sensor. The heaviest racket of the speed series with all the outstanding characteristics that set a top-notch racket apart. The world class player, Novak Djokovic, who plays with this racket, also enjoys these characteristicsThe Speed with its 18/20 string pattern guarantees optimal control and exactly the feel aggressive players look for. Technologies:Graphene XT: A new era of Graphene with even more power. The improved structure of the Graphene XT increases the strength in the centre of the racket by 30%, guaranteeing optimised weight distribution. The strong and super-lightweight material ensures a much better manoeuvrability of the Head rackets. This model, the Head Graphene XT Speed Pro 18/20 Tennis Racket, is compatible with the Sony Smart Sensor. Enhance your tennis game and analyse your racket with the new Sony Smart Tennis Sensor. See your shot data in realtime. Watch a video of your game with an analysis of the shots – right after the match or in realtime. Review your game using the analysed data after your match or training. Share your results with friends. Simply remove the device in the end cap, insert the adapter, screw in the sensor and carry on after logging in. You will find additional information under article number: 1297230000800000