Use Jugs(R) Sting-Free(TM) Dimpled Baseballs for maximum accuracy and performance in your pitching machines. The 12 pack of B1000 balls are the same size and weight as leather baseballs and feel like leather balls when hit, but they will not dent aluminum bats or sting the hitter's hands. The Jugs(R) Sting-Free(TM) Dimpled Yellow Baseballs can be used in most pitching machines for more efficient batting practice. FEATURES: Cover : Yellow dimpled synthetic material for maximum accuracy and performance Core : Feels like a leather ball when hit Technologies : Will not dent aluminum bats or sting hitters' hands Additions : Same size and weight as regular leather baseballs League/Certification(s) : Practice only Balls included in purchase : 12 (dozen) Recommended use : Most pitching machines Manufacturer's warranty: : 1 year Model : B1000 Jugs For additional information relating to the Manufacturer's Warranty, please contact 1-800-547-6843.