Adult tennis racket head size midsize racket head size 626 cm head size inches 97 sq in stringing 16 x 20 level professional type of racket tournament racket playing properties control power spin recommended height from 155 cm weight unstrung 270 g racket balance even grip size l1 l3 shape oval frame profile min 22 mm frame max 22 mm length inches 27 technologies yonex isometric yonex 3d vector shaft yonex super cushion grip se