What is 100% of power for the forehands and the backhands? Babolat August 04, 2018 16:29 Updated Follow 100% of power is almost equivalent to 220 km/h (75 mph). If you want to know why the PLAY racket cannot give an exact ball speed, click here . Related articles Why do we only have a percentage of power, and not a speed (in km/h or mph) for the forehands and backhands? How can the racket tell if I hit a first serve, a second serve or an overhead smash? How is the spin effect percentage calculated? My racket doesn't switch on, why? Pure Aero PLAY Characteristics Comments 0 comments Article is closed for comments.