Head Gravity tennis racquets come with a massive sweetspot, comfort, spin and stability. The Gravity Pro comes with a condesnsed 18x20 string pattern. The rest of the line, including the Gravity MP, come with a more open 16x20 string pattern. Graphene 360+ combines Head's Graphene 360 damepning technology and the all new Spiralfiber technology. Spiralfibers flex, untwist and retwist increasing overall flexibility ensuring a smooth and comfortable feel.