Head Youtek Four Star The HEAD Four Star racquet is an upgrade from the base model Three Star launched earlier this year. The Four Star utilizes both inner and outer QuadFace technology for increased and consistent power, along with enhanced control through a 2 piece Control Ring. This combination provides both the power and control you want in a super oversized lightweight racquet. HEAD also incorporates proven YOUTEK technologies into the new Four Star racquet including our proprietary d3o material which allows the racquet to adapt to every shot you hit. Best suited for players with shorter, compact strokes looking for power. Recommended for the 2.5+ NTRP level players. YouTek: YouTek combines superior technologies to perfectly match your individual needs. Whether your game is aggressive and adventurous or consistent and smooth, YouTek™ enhances your performance and brings out the best in you. d3o: The frame-inlay d3o™ is a smart material. The specially designed molecules in d3o™ react on different impacts within nano seconds. They stay soft during slow hits and lock together on hard strokes. With this behavior, d3o™ is able to sense the needs of your play and adapts to you. It provides maximum power as well as softer touch for a better feel.