The ultimate hitting and training aid to develop quick hands and faster bat speed. It is a balanced wood training bat for teaching players the proper swing techniques. The Hammer will strengthen wrists and forearms and with work… increase bat speed. The different lengths of Hammer depend on age strength and size. The 21" Hammer - Recommended for Younger players. The 24" Hammer - Recommended advanced/strong players. Older and stronger players use the Hammer for one-handed drills/Younger players use two hands. All Hammers include a drill sheet.