Description:he Head YOUTEK Radical Lite Tennis Racquet is a lighter, more powerful version of Andy Murray’s weapon of choice. It provides a great combination of power and control. The YOUTEK frames come with d30. d30 is a smart material that has abnormal behavior characteristics. More specifically, d30 changes its behavior when you are hitting a tennis ball. These racquets are designed to flex more on slower hits providing exceptional feel and less on faster hits providing more stability and power. Integrated in the lay-up and positioned in the shaft area, d30 maximizes performance and offers new possibilies for players.