Used by WTA pro player Flavia Pennetta the Wilson Steam 99 offers a nice blend of spin, power and precision. The feel is enhanced by Wilson's Amplifeel 360 technology, which is designed to provide a cleaner impact with reduced shock. With a strung weight of 11.3 ounces, the Steam 99 will give intermediate and advanced players enough maneuverability to stay on offense. The extremely controlled response enables ambitious targeting while also helping to minimize overhitting. To enhance spin this one comes with an open 16x18 string pattern and a head light balance. Taken together these specs add up to fast swing speeds and major bite. On groundstrokes our TW playtesters found easy access to spin along with decent comfort and controllable power. At net this one has the right combination of maneuverability and stability for both offense and defense. The excellent spin and control allow for aggressive targeting on serves. All in all, the Steam 99 is great option for the 4.0+ player looking for controllable power and above average spin potential.