Wilson Triniti Tennis Balls are the first eco-conscious, high performance tennis ball designed with 100% recyclable packaging. Featuring Engage core which has a thicker wall making the ball more resilient and reduces deformataion. The core maintains ball liveliness 4 times longer than a standard core. Also features STR felt which is 50% more flexible than standard felt to provide enhanced feel. 5% of the profits support worldwide sustainability efforts.