The INDESTRUCT-A-BALL is engineered to keep their shape and prevent cracking like standard practice balls, even after thousands of hits. The proprietary formula was created to flex on impact to prevent cracking along with reducing travel distance. 12in. Training Balls Extremely durable and built to last thousands of hits Provides hitters instant feedback on contact Limited-flight design for easier retrieval Includes a reusable drawstring travel bag Lab tested to last 5X longer than traditional plastic training balls Engineered to flex on impact to prevent cracking and reduce travel distance For use with all bat types The material automatically retains shape after hit Franklin MLB Indestruct-A-Ball 12in. Training Balls - 6 Pack.