Sticking with tradition, the device's back is an all-Kevlar affair and it feels great, conferring just the perfect amount of friction and grip so you won't have to worry about accidental drops.

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That lack of friction, combined with extraordinary sideways grip, means an iceboat can sail six times the speed of the wind.

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But on a high friction surface like clay, the ball will grip more and change the trajectory of the ball quite significantly.

BBC: SPORT | Tennis | Rules and Equipment | On the rebound