Baseballs Material: Made of durable soft plastic that prevents cracking and deformation; the lightweight design of the ball makes it easy to use, which won't break windows or damage property; the material has gone through tests Regulation Size: These plastic training baseballs' circumference is 9 inches and 2.75 inches in diameter, but weigh much less; limited flight designed to flex on impact to reduce flight distance, and get a more realistic flight when hitting and pitching Pop-Back Tech: These training balls have 26 hollow holes, the uniform holes provide maximum accuracy; the great thing about these training balls is flexible design retains shape and prevents cracking, they'll pop right back into their original shape, even after many times of hits; these balls are more durable than traditional plastic training balls Fun for All Skill Levels: Teens and adults alike will love these highly durable baseballs, you can use them for pitching, batting, throwing, and catching practice to improve your baseball and softball game skills Multi-use: These balls for sports baseball tee work and softball training, indoor and outdoor games, pets training The regulation-size practice baseballs are made from durable soft plastic preventing cracking and deformation, 2.75 inches in diameter, set of 12. These training balls have 26 hollow holes, providing maximum accuracy, and their limited flight design can reduce flight distance and get a more realistic flight when hitting and pitching, popping right back into their original shape even after many times of hits. Teens and adults can use these highly durable baseballs for pitching, batting, throwing, and catching to practice indoors or outdoors to improve your baseball and softball skills.