The throw angle is the angle that the ball flies off the racket from your stroke. For example, when you perform a topspin loop stroke, a high throw angle rubber will propel the ball higher, and a low throw angle rubber will propel it lower. So with high throw angle rubbers you often have to adjust your stroke to be lower to compensate for the high throw angle. And for low throw angle rubbers, you have to swing higher to get the ball over the net.
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