Head Graphene XT Instinct MP Tennis Racquet - Unstrung Head Graphene XT Instinct MP is endorsed by Maria Sharapova. It features a combination of power, maneuverability, and precision. Head Size: 100 sq. in / 645.16 sq. cm. Length: 27 in / 68.58 cm Weight (unstrung): 10.6 oz / 300 grams (strung): 11.1 oz / 315 grams String Pattern: 16 x 19. Racquet is strung and ready to use.