Louisville Slugger Training Bat 28 inch 2-Hand 1-Hand : The Louisville Slugger One-Hand Trainer may be small, but for the serious coach andor player, its usefulness is unmatched. This 28" training bat is used for tee and soft-toss drills to aid in hand-eye coordination, bat control, as well as top-hand strength. The One-Hand Trainer is used by numerous hitting instructors to help teach players the importance of "throwing" the top hand and gaining extension through the hitting zone throughout their swing.