Sony has confirmed that the Smart Tennis Sensor revealed earlier this month as a concept at CES in Las Vegas will be going on sale in Japan in May, priced at 18,000 yen (£105).

The Smart Tennis Sensor simply latches on to the bottom of your tennis racket, almost inconspicuously, to stream data to your smartphone over Bluetooth, giving you on-the-fly data about your swing. 

An app for either iOS or Android will tell you how fast the ball is travelling, thanks to vibration and motion sensors, what kind of swing you performed, the amount of spin you applied to the ball and a breakdown of the performance of your swing. Essentially, it wants you to become a pro.

At launch the Smart Tennis Sensor will attach to the Vcore Tour G, Vcore Xi 98, Vcore Xi 100, Ezone Ai 98, Ezone Ai 100 and Ezone Ai Lite tennis rackets.

Sony says it plans to support more rackets in the future, but it doesn't go as far as saying which racquets or when. 

Sadly for the rest of the world, there is no word on when the sensor might be coming to those outside Japan.