The Pro Kennex Ki 10 290 continues their tradition of featuring armfriendly technology that can help or alleviate players tennis elbow With multiple groundbreaking technologies the Pro Kennex Ki 10 290 has added power and spin to the already outstanding comfort benefits the brand is known for By segmenting the Kinetic Moveable Mass and placing it into the four corners of the racquet head Quadfocused design increases the frames torsional stability even further moving the sweet spot higher in the string face as the mass of the frame moves higher the sweet spot follows it By stabilizing the frames corners it will deflect less increasing power and spin production simultaneously Additionally the specialtreated spiral carbon offers improved dampening properties while the high modulus graphite provides strength and needed rigidity