Adult tennis racket head size midplus racket head size 645 cm head size inches 100 sq in stringing 16 x 19 string tension 26 28 kg level advanced type of racket all round racket playing properties control power spin balance 330 mm recommended height from 155 cm weight unstrung 284 g racket balance head light grip size l1 l3 frame materials carbon glass fibre basalt shape oval frame profile min 26 mm frame max 26 mm length 685