Diamond DMPB Machine/Batting Practice Baseballs Built For Repetitive Use Diamond DMPB Machine/Batting Practice Baseballs are designed for repetitive use with pitching machines during batting practice. These training baseballs feature full-grain leather covers with a cork and rubber core. Abrasion resistant low seams are reinforced to withstand constant use and feature dual colors to easily identify them for use in pitching machines. Keep your hitters sharp throughout the season when they practice with these batting practice baseballs. Diamond DMPB Machine/Batting Practice Baseballs feature: * Features durable full-grain leather cover * Abrasion resistant reinforced low seams * Seams are dual color for easy identification * Yarn winding * Cork and rubber core center * Quantity: 1 dozen * Pitching Machine baseballs for any age